But, as another person commented, the overhead around government projects (documentation, reports, meetings, etc) will bloat things beyond a simple time/materials development contract.
The FBO has a site listing the contacts, but there are actually some pretty interesting projects that pop up to be bid upon. Only downside for someone new to the process (or a small shop) is that the big boys (SAIC, etc) have this part pretty streamlined as well as sometimes having in's with the agency requesting the proposal.
Edit: The site -- https://www.fbo.gov/
So typically people will order the most expensive things that can fit within the budget or even buy stuff they don't need just to spend all the money.
This does strike me as often wasteful but I don't see an easy fix.
You meant doubleplusungood, right?