I had one of those three letter, two number, and one more letter addresses at prodigy.com. Something in the form of
abcd12e@prodigy.com, but I can't remember my specific address.
Back in 1991 or '92 I think.
I was always envious of the AOL people who got to choose their address, whereas we prodigy people were assigned ours. In the long run, however, I was happy to see that AOL turned out to be a much crappier ISP.