I've signed up to as many as I could find.
theres one that I didn't feel like going through the sign-up process when I found it, and now I do, but can't remember it, I'll find it again soon. a couple are pending as the process is e-mail invites.
check
http://opticbit.com/active/bitcoin.html for my upto date list about 20.
CampBX Exchange
Trade Hill Exchange
Bitcoin7 Exchange
TripleMining Mining Pool
Mining4Lindens (mining pool sortof)
Krad Miner Web GPU miner
BitCoin Plus web CPU miner
Operation Fabulous adsense with btc
Bitcoin Bonus Affiliate payments (up again)
SMS Dragon Txt Service
BitCoin Toss 50/50 gamble
Flip for Bits 50/50 gamble
Double Trouble 50/50 gamble
BitCoin Darts gamble
BTC Kamikaze gamble
Streight Line Doubler Ponzi
BitCoin Randomizer Ponzi plus advertising (down)
Paid to Surf get paid to surf (down?)
BTC Bubble ponzi plus ads (down)
Triple Mining, and Camp BX are the newest I've joined.
I made the most off SLDoubler when I was advertising it on BTCBubble. getting .2 BTC per referral.
however I had to pay 1BTC to join, and it still hasn't doubled and won't for months if ever. but I have gotten more than 5 referrals on it.
Bitcoin Bonus has paid me the next most, I haven't kept track but it was paying quite a few btc till the value shot up to 30 USD.
the gambleing have paid out small amounts
the web cpu miner is running slowly, but I get a few fractions of a bitcent every day. If I had more traffic it would be better.
the web GPU miner is not paying out much since not many people have web cl installed, and currently they have to click my link, where the cpu one they just need to have java running when they load the page.
Places I've advertised.
Bitcoin Forum sig, drives a majority of my traffic.
Witcoin fairly good
millionbitcoinhomepage did ok
BTCBubble worked good for gambling type links
Twitter works good for traffic but not btc spending.
Bitcoin Classifieds got a lot of trafffic.
a TOR forum got some traffic.
my own site.
Blackhatworld/dp/wso good for the gambling links.