Eh. You can get like a $200/hr rate. If you're a small company with low overhead, you can get paid quite competitively with the private sector in base comp. Difficult to match big G stock grants, though, no one is becoming a millionaire off of this work.

Unless of course what you do on the grant can be turned into a billion dollar company, because (generally) contractors walk away from research programs with liberal rights to the IP they create, with the government retaining some rights to use, but very rarely (IME) retaining direct ownership. Of course, it's probably not that likely that what you do can turn into a billion dollar company but hey, one can dream...