I dunno. His sense of humor was really attractive and I liked his writing style...and I read them as an adult. My copies are still in UHaul boxes, so they'll have to wait. Somebody mentioned Faferd and the Grey Mouser...it took me all night to remember Fritz Leiber. I re-read "Ill Met in Lankhmar" a few years ago. It didn't hold up as well for some reason. Same with Robert Howard's "Conan" stories (which, as a teenager, I thought were excellent). Burroughs' Barsoom stories were fun, but I only read them when the last movie came out...so they were not really teenage memories being re-assessed. Another favorite writer of mine is Alan Dean Foster. I tend to like writers who have a 'universe' and write within it. His "Pip and Flinx" series needs re-reading. I just finished re-reading his "Icerigger" trilogy just a few weeks ago. It has held up nicely...and is a great page-turner. Another trilogy in the SF game is James P. Hogan's "Giants Star" series. Great writing with a 50s and 60s vibe. Has held up well. Fantasy includes "alternative history" as a subgenre. I often read stuff in that vein. Eric Flint's "1632" series, Turtledove's stuff, etc. I would guess that H.Beam Piper's "Little Fuzzy" series would be included in Fantasy. Great writer!