Have you read the sequel to Mote, The Gripping Hand? If not, do so immediately.

There are so many great sci-fi books, I can't even begin to list them. Look up the Hugo and Nebula awards -- you can't go wrong with books that have won (or even been nominated) for them.

Yes, read the "Gripping Hand" if you liked the first Moties novel. I read all the sequels to "Ringworld," but they didn't impress me as much as the original. Still worth reading though, if you're a Niven fan. I'd also recommend "Footfall" and "The Legacy of Heorot" as two of his better novels outside the Known Space series (IIRC he co-wrote Footfall with Pournelle).

The best hard sci-fi/space opera I've read since the old Larry Niven days is by Alastair Reynolds. He's sort of a darker, edgier version of Niven. I'd recommend starting with "Revelation Space." If you like that, then read the other two books in that series: "Redemption Ark" and "Absolution Gap." I enjoyed his other standalone novels and short story collections too, like "Pushing Ice," "Century Rain," "Zima Blue and other stories" etc. Reynolds is a retired astrophysicist, so the science extrapolation in his books is very good.

Actually, now that memory is jogged, I remember liking "Rendezvous with Rama" alot too. And the Foundation trilogy I seem to recall enjoying a lot, in fact I think I maybe liked it a whole lot, will have to look back at that one as well as the Moties. Funny though, 'Rama' and 'Ringworld' are 30 years later somewhat mingled in my memory, and really any of these I could read again and have no clue what would happen next! And I almost forgot the book Starship Troopers which was just so much better than what Hollywood did to it (rented the sequel and I call it Starstrip Troopers II, that is a mouthful if you say it quickly). Yeah Dune is obviously a classic just I read it when I was home sick for a week and then it was ruined for me by the first movie that came out way back when, plus the trilogy kind of got worse as it went on, at least for me. That said I have been watching the more recent video version with the wife and she seems to like it.

I much more recently (only 10 years ago) read "On Death Groud" but I have to say I did not really like it much, should have been the kind of book I like but just did not for some reason.