My current car is a 2004 Saturn Ion. I am pleased with its performance, since I expected it to be slow as hell (high 16s to 17s). My highly accurate stopwatch-while-I'm-driving-past-landmark tests have yielded approx. 1/4 mile times in the very high 15s, which sounds about right.

So far, I have kicked the asses of:

Cavalier - they almost blew it up
V6 Eclipse - I pulled a little farther away in every gear
turbo DSM - really old and worn out (1st gen?), poor thing would barely go
Mustang V6 - with a bad driver
Neon - on takeoff and from a roll
F150 - wiped shat-eating grins off rednecks' faces
2003 Taurus SES - raped it from 30-80 MPH, she was pissed, tried to run me off the road

Tied with:

some kind of Integra - neck and neck until I accidentally hit the fuel shutoff in third gear, he thought I shutdown and quit as well
2003 Mustang V6 - with a better driver, he still had tirespin at launch

Ass kicked by:

Some kind of Audi - he chirped the tires, had a lousy takeoff, then blew by my at 40 MPH like I wasn't even there
Mustang Mach 1 - thought it was another V6, ouch

I'm going to get the SMS turbo kit, a boost controller, and BOV, and see how that works out. I'm not trying to be the fastest, just fast enough to surprise a few people.