Used Compuserve, Prodigy, and AOL (mostly Prodigy) all before they became ISPs, in the 80s and early 90s, but that doesn't count. Did continue using Prodigy for awhile after it started offering Internet access though, though never used them as an actual ISP. Started using a local freenet in the early 90s too, but that's not really an "ISP" either, though it did give telnet and gopher access from their system. (And www via Lynx and Slipknot later.)
First real ISP was an AT&T thing called "Worldnet" around 94 I think. Then used a local dialup ISP for a few years until TimeWarner started offering cable modems in 1998. Lived in a college dorm 2000-2001, had Speakeasy DSL the rest of my time at college, after graduating have had cable via various companies: had Cox for a couple years, then briefly Adelphia right before they got bought by Comcast, who I still have now though I dumped them for TV years ago.