I was laying in bed last night and I heard on a TV show, I have no idea what show, that these cars can go from 0 to 100 mph and back to 0 in 7 seconds. Is this really true?
According to Motor Trend’s test of a '96 model (with the somewhat misleading front-cover-headline “840 Horsepower Honda!”), it’s pretty close: 0-100 in under 7 seconds (4 seconds to 60, and another 2.7 seconds to double that). They don’t say how long it takes to stop, other than implying that it’s just as neck-straining as the acceleration. Not bad for a 1600-pound vehicle with well over 800 hp (840 is all Honda would abmit to, but that’s a conservative figure and has surely gone up since then) that you can’t see out the front of…
Apparently those figures Gunslinger are correct for 0-100-0 in 7 seconds provided there is a brick wall on the course 
The 7 second number is probably correct for a Formula 1 car, but may not be realistic for a Champ car (nee Indy Car) or the IRL (current IndyCar).
F1 Cars have similar (if slightly less) horsepower than a Champ car (what Gunslinger was talking about), but they weigh much less, and their brakes are far superior.
In 1998 a British TV show tested a Jaguar F1 car and claimed a 0-100-0 performance similar to the 7 second figure the OP mentioned. No cite, though, sorry.