In PA, i receive cash assistance and food stamps. Is it necessary to file income tax?

I had no income in 2007 except for the cash assistance, which started in October.|||it you get Welfare and food stamps NO you don't have to file Taxes..or will you be Illegible for a Rebate|||I don't think so because MY taxes that I PAID are supporting you. So if you filed, I think that would be like taxing me twice. I wouldn't appreciate that.