Cave Story. Greatest retro game.
They're both rougher than a rusty razor, but I definitely enjoyed Sonic Adventure Dicks better than SA2. It's still pretty bad, but with enough vigorous polishing, it could've aged much better.
Also, I played some Legend of Zelda: Link's Awakening Dicks on Gameboy the other day. Quaint game, but ages like a fine wine. Reminds me of a transitional phase between Legend of Zelda and A Link to the Past that isn't Adventure of Link.
Right now I'm playing some Mega Man Zicks. It's ... not bad. It just feels like a misguided sequel to Zero 4. The shitty mission structure ripped straight from Zero 1 gets in the way of the non-linear exploration aspect, which isn't that rewarding as is. The meat of the game--the levels--are actually pretty good, but everything in between feels ... plodding. I mean, you're free to run around and shoot/slash stuff, but there's really nothing to do other than collect those [tornado fang]ing fun data disks. The lack of flow and choppy fun just kill the game for me, and you couldn't have followed up the two decent intro stages worse than with the hide-and-go-seek bullshit in the residential district. Man, that's some hardcore guerilla hazing action right there: go duck under holes at the speed of molasses and find the trained Guardian troops who totally aren't babysitting you.