Users can pay an additional monthly fee (2 and up USD) and be eliegilbe for a portion of SL economy profit sharing in $L.
The more money you invest, the higher percentage your return will yield..assuming that SL morket is making a profit of course.
The additional funds might help Linden Labs get fasster equiptment, and Slers could enjoy taking part in the actual company.
Groups could also participate..each member pays a small portion added to their account fees, and the group receives $L in return.
Each user/group-member on the list could be delivered a statement via email or IM (user choice).
This of course leads right into Stock trading in SL.

Land value, clothing markets, gaming markets, real estate markets, groups, and of course $L!
I am not sure how well bank loans would go over..
do an SL credit check ..must be member in good staning, have decent rating and automated math to do somet stuff with acocunt transaction history should be able to tell weather this individual or group will be able to repay their loan, what interest rate they could get, etc. Automatic deduction of payments from the stipend starting two weks after the loan is disperesed. (restrictions apply, cannot use to buy more than a set amt of land, etc)
Could also lead to virtual stock market ticker..like a large LED banner above town hall.
LOTS of code, LOTS of work, but might increas profits for LL and enhance experience for SLers.