Toyota doesn't really have a new-model performance car, yeah don't hate me for that. I know the V6 camrys' & solaras are quick. But as far as off-the-lot peformance it isn't there.
A Scion tC w/ a supercharger sounds nice. A big plus there is that Scion will warrenty the TRD s/c. A new tC is about 16,000 and the TRD s/c kit is about 4,000 average plus dealer labour to get it installed under warrenty. So thats about 20,000$. 20K for a s/c tC with about 200 Whp is a great thing to consider.
Another great car as Cyorke mentioned is the Lexus IS300. Browse autotrader.com for a pre-owned IS300. I found an '02 IS300 on there for only 17,000$. And it had the 3.0 I6 w/ a manual tranny. Yeah thats a lot to pay for a used car but thats a great car. 215 HP, manual, Rear-wheel drive, lexus luxury, ect... There are s/c kits for the IS as well as turbo kits out there that can put down some power.
Between a s/c scion tC and a s/c IS300 i would go for the scion
EDIT: but that all depends on your budget