So after LordKaT suggested the idea I started to think of some games that could possibly make use of this and what prizes could be done;

Games -

Starcraft 2 - StarCraft 2's multiplayer was specifically designed for e-sports, it has everything you could possibly need to stream it online. Starting up tournament brackets would require very little effort, if anything all you'd need is a caster unless you intend to do it yourself.

Call of Duty - Same as above, the general game for CoD tournaments is Search and Destroy. Could be team based, or you could make it 1v1.

Civilization 5 - I'd suggest for time sake keep the game mode to be Time based so only a certain amount of turns could be used, unless you want it to last longer that is, 5/10 people in a game, highest points win etc.

Team Fortress 2 - I don't play TF2 so I'm not sure what kind of e-sports is supported.

Prizes -

For prizes, it could range from very basic things like a signed photograph or be invited onto the stream.

Slightly more personal towards LK would be the offer of goods, offering to buy them a steam game up to a certain cost, time cards for a game (i.e. WoW).

Even more interesting ideas would be to offer a guest spot on a podcast for 1 or 2 weeks, joining you on an episode of TTT, Dr 8 Bit, Tabletop shop or whatever, you could even go as far as to offer a guest spot in the Wyrmwick campaign for a few sessions. It probably wouldn't take much effort to work a temporary character into a story, but that would of course be at your discretion.

These are just a few ideas, still not quite worked out the kinks but hopefully this might give you some ideas to work with.