1. This was a favorite setting of T. Mark Hall when he played online games. It offers fast play, and also the possibility to selectively take some time to think a bit longer about a particular move. It encourages you to use your time wisely.

2. Less emotional investment - losing is not so painful: Making a blunder late in the game after having played for an hour and a half feels a lot different than making that blunder at a similar point in the game after 10 minutes.

3. It is a good opportunity to try out new ideas: Want to do that great wall? Go ahead!

4. You get to play a larger variety of players: This is a big one. I have had games against 9ks and 3ds. This almost never happens when I put up a slow game offer.

5. It generates great material to review. Particularly when playing stronger players, you get tons of examples of how they manipulate you. Taking the time afterwards to examine these methods and tricks is very instructive.

6. You get in more games. You can squeeze a game or two in during your lunch break and still have time to eat.

7. No cheaters: The games are too fast to consult outside help.

8. You don't have to sit on your hands or otherwise feel bad about playing too fast. Of course you will make bad moves, but you also learn not to dwell on them or chide yourself for them. Instead, you look for another opportunity elsewhere.

9. It is good practice to improve your concentration when you are under pressure.

10. Playing blitz is fun - isn't that what we are here for?

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Patience, grasshopper.

Interesting. (you saw in my study journal that) I played a few blitz games today and had the (mis)fortune to play a 2-dan and an even higher ranked dan player. Needless to say I got completely destroyed, but I'll definitely look into those games and I'll probably learn a few things on why their moves were so much better.

Playing blitz is definitely fun and losing isn't as bad, but I also think it can be dangerous if you do it too often, reinforcing bad habbits and whatnot.