My answer: 24 different tokens. Not that they all have that much value.. I think I've bought 4 of those, with the rest being airdropped. Surprisingly a few have been worth several dollars.

My favourite of the lot is DEC, which so far I've had the most involvement with. Earning playing Steem Monsters and spending it to received Mystery Rewards, and potentially spending it on Guilds, it is the most utilised of my 24 tokens.