That's right. It happened and I was shocked.
Let me first say this is a long-ish story, but I think it's a great one.
I was driving along on the highway going home from Boston before the winter. It was near 1am and there wasn't a soul on the road.
After a while I notice the only car out is what appeared to be a Vette, holding 6 lengths behind me in the same lane as me (middle of three). Just to be sure it was a Vette, I had my buddy in the passenger seat look behind me to make sure it wasn't a Statie pacing me (common in MA) and he confirmed it was a Vette.
After a while we were coming up to a minivan driving in the slow lane and I eased off a bit to let the Vette catch up just so I could see it. Oddly enough he opted to pass me on the right and the minivan was only about 100 yards ahead in that lane. As he got even with me I dropped into 4th and jumped forward a bit, blocking him behind the minivan. I wasn't planning on racing him, I was just horsing around a bit.
Clearly he took this as a challenge (not that I wouldn't) and he pulled back into my lane right on my rear bumper. The moment we were a car length past the minivan he flicks into the right lane and went for it. I dropped to 4th again (should have selected 3rd) and went WOT. Since he got the jump on me, I matched his speed just as his rear bumper was even with my front. To my surprise I kept exactly one length behind him like that all the way up to quite a speed (not sure if I'm allowed to or if it's a good idea to post the actual speed reached here). He then backed off, so I followed suit. Essentially the race was a draw.
I dropped down to normal highway speed and he kept going a little faster. Then I saw him take the exit I was going to take so I gunned it to catch up with him at the toll so I could wave. I caught up and rolled down my window. I waved and gave him a thumbs up but he had heavily tinted windows, so for all I knew he wasn't into honorable racing and could have been flipping me off.
I pulled out of the toll and went on my way. Then he caught up with me at a traffic light. He pulls up on my right and rolls down his window. I didn't know if he was going to say "good race," or shoot me. I rolled down my window to have a guy in his 50s saying "Great race! You've got a real nice car there! Good job, have a good night!" I waved and said "beautiful car, you too," and we went on our ways.
Mine is a bone stock 04 WRX and this was a 50th Anniv. body style Vette. It was an amazing experience either way, but I would have thought a Vette would be better matched against an STI in a drag race. I can't understand how my WRX held even with him.
As a side note, this was the only time I've ever actually raced someone. I don't find it worth the risk to get up to those speeds. Usually if someone in a Civic or an Acura or something tries to challenge me I'll just push ahead of them real quick to show I have more power and then I'll back off.