Not in any real order and subject to change
1. Battle Kid - A homebrew game, but it's already two years old and earns a place on the list; Battle Kid 2 will probably knock it off.
2. Mario 3 - Just too addictive to run through the last few worlds with the Hammer suit.
3. Little Nemo - Animal friends give it variety.
4. Moai Kun (Famicom only) - Sideview single-screen brainteasing platformer.
5. Recca (Famicom only) - Ridiculously fast vertical shooter with lots of gimmicky effects.
6. Gargoyle's Quest II - This should've been all platforming, but at least the gliding is solid.
7. Uforia/Hebreke (Released in Europe) - Although I didn't see the point of having four characters (Their abilities could be condensed into one without affecting the control scheme), it's a cute Metroid-style platformer with some great NES music.
8. Vice Project Doom - Eh, maybe not top 10 material, but it's a blend of Spy Hunter overhead shooting, hack-and-slash action and even some Operation Wolf-like first person shooting and the controls are fluid enough to make it all entertaining. Plus the cinemas tell a dark story with goofy writing.
9. Tiny Toon Adventures - A lot more fun than any Looney Tunes-licensed game; pretty much up there with the Capcom Disney games.
10. Adventure Island IV - This is almost Super Metroid-quality in game design. Am stuck on it, though.