Person to person microlending.
- "P2P microfinance service Milaap.org reports the milestone of 10 million indian rupees (approx 190,000 US$) lent in 18 months with a repayment rate of 100% so far." 
"Kiva Zip is an experimental site facilitating direct p2p microfinance loans without any intermediaries. The original Kiva model relies on MFIs (microfinance institutions) which locally validate borrower request and disburse the money and collect the repayments.
Kiva Zip eliminates the intermediaries directly connecting lender and borrower in person to person microlending. This will reduce interest rates for the borrowers (which during the initial testing phase of Kiva Zip pay 0% interest). The use of direct electronic and/or mobile payments further reduce the costs of the loan transactions." (http://www.wiseclerk.com/group-news/servicesmicrofinance/kiva-zip-enters-direct-p2p-microfinance/)
Here is how the regular Kiva system, which is not p2p, really works:
Sander Van Damme:
"The system is quite simple: Kiva is in contact with several field partners all over the world which are currently funding microfinance projects but lack the funding to scale up and reach more customers. Kiva then looks for individuals in developed countries that want to provide interest-free loans to these institutions and help them reach their social goals. Lenders select projects online that they want to refinance. This means the loans have already been disbursed to micro-entrepreneurs and the choice of funding is therefore not made by the lender but rather by the field partner itself. Kiva sends these funds to the microfinance institutions who can subsequently lend these funds to other borrowers; the lenders' payback however depends on the projects they have chosen and whether or not these entrepreneurs perform well. In return for this free loan, the field partner puts information about the borrowers, their performance and how the loans impact the people's lives on the internet portal." (https://www.zidisha.org/editables/news_docs/Louvain.pdf)
The Future of Peer to Peer Microfinance
Sander Van Damme:
“It remains hard to tell how peer to peer microfinance will evolve; Zidisha is only a small website which currently only has a very local impact. However, given the current success of altruistic platforms such as Kiva, able to finance $231 million in loans since its launch in 2005, it is clear a big potential for such websites exists. The only constraints to growth that remain are the current small portfolio of prospecting borrowers and the limited geographic focus. The platform is currently working on this second point by offering new applications from Indonesia and Burkina Faso. Furthermore, the growth of mobile banking is an important factor for the operational model of getting the money to the most remote borrowers in rural areas.
As discussed above, Zidisha presents itself as a clear model for real peer to peer microfinance, based on computer-literate entrepreneurs with credit history and philanthropically motivated lenders. We can foresee more such platforms to develop as mobile banking becomes more widespread, and see it as a logical evolution in line with developments which the Irish Loan Funds and the English Friendly Societies also experienced: as microfinance institutions develop a credit history in developing markets, others will be able to profit from this and take away their most successful clients. Of course the platform is very young and only very few loans have currently been repaid, it remains therefore to be seen how lenders will react when loans default and their money is lost. We foresee this to be a very important test for the platform and urge further research to keep track of this evolution and its possible implications.” (https://www.zidisha.org/editables/news_docs/Louvain.pdf)
See about the prehistory of (p2p?) microfinance: Irish Loan Funds
Recommendations by Kevin Kelly in Cool Tools
(I'm not sure these are actually 'p2p' microfinance - mb)
Kevin Kelly at http://www.kk.org/cooltools/archives/001484.php:
"there are many other outfits that offer individuals (like us) ways to leverage as little as fifty dollars via micro-finance programs online. Unleashing compounding good is only a few clicks away. Make a loan, or outright grant, using your credit card, or even PayPal.
Inspried by the original Grameen Bank in Bangladesh. Minimum contribution, $100. One of their projects is Village Phone -- cell phones that women buy on loans and then can rent to others for income. "The Village Phone program in Uganda, the first of GF's efforts to replicate the pay phone program outside Bangladesh, continued exceeding expectations in 2005. More than 3,500 microfinance clients have bought and now operate a Village Phone as "Village Phone operators." Besides the boost to operators' incomes, the program is creating a national telecommunications network. Of Uganda's 56 districts, 53 now have at least one Village Phone operator. Often, Village Phone is the first local telephone that villagers have. Having a quick means to communicate has contributed to higher levels of productivity, savings, and safety for entire communities."
This is one of the most direct person-to-person micro-lending programs. When you give to Namaste Direct, you are informed of the person who receives your loan, how they used the money, and their progress. ND can also arrange a visit to the lendee -- this will turn your loan into a life-changing experience for you as well. But because of this directness the giving area is limited -- currently to Mexico and Guatemala. No minimum contribution.
FINCA Village Banking
FINCA makes loans directly to the poorest villages. They aim their lending to 10-50 neighbors who come together to form a village banking group, and who in turn decide who should get what and how much. FINCA specializes in small loan amounts ($50-$500) for the very poorest. The minimum contribution to their program is $50. While a few hundred dollars is powerful, with only $5,000 you can start a whole village bank for micro-loans, thereby compounding the power of micro-finance to an entire small community.
Minimum contribution, $100. Since they accept PayPal, I found this program really easy to contribute to. (Get with it, others!) Unitus, like Accion below, funds other local micro-finance programs, rather than direct loans to individuals. "Unitus seeks to identify highest-potential emerging MFIs (Micro-Finance Institutions) and help them to achieve exponential growth."
Accion is an umbrella institution providing technical assistant to local micro-lending institutions. Minimum contribution, $50."ACCION is leading the effort to make micro-lending financially self-sustaining. Micro-lending programs have the potential to cover their own costs. The interest each borrower pays helps to finance the cost of lending to another. In most poverty alleviation efforts, every person helped brings the program closer to its financial limits. Successful micro-lending programs, on the other hand, generate more resources with each individual they help. As a result, well-managed micro-lending programs generate more income than they spend. Once they become economically viable financial institutions, they have the ability to access a virtually unlimited source of lending capital - the billions of dollars invested in the world's financial markets. Several of ACCION's partners have already made the transition from nonprofit, charity-dependent organizations to banks or other regulated financial institutions."
Kevin Kelly also discusses others on his blog:
Opportunity Int'l, http://www.kk.org/cooltools/archives/000230.php
Heifer, his favorite, at http://www.kk.org/cooltools/archives/000231.php