Thanks a lot for sharing your plugin with us, It is a great step towrds monotizing our QA websites. It is very creative rewarding participants. I haven't tested your plugin yet, just have questions in mind like is it integrated with paypal etc or ?
As for your question:
One thing which is still missing here is a plugin to let sponsers to post their ads ( banner) on our q2a website. Someting like this:
1- the admin to speciify the banner sizes and some spots (grids) on the question page ( on the side bar etc) or front page for placing ads and as well specifying the price for advertizing at those locations ( per month/ per week etc)
2- a user (sponser) can login, select one of those spots and see how much the price is for advertising at that spot, uploads his/her banner. Then selects the dates at which he want his ad to appear, then checks out and pays via pay pal etc.
Thanks again for sharing your great work