It's free.
It only takes a few seconds.
You can post in the forums.
You can see "The Hole" in the forums.
You can post reviews.
See all those boxes on the front page? YOU decide which ones to collapse so you don't have to look at them!
When we have contests, they'll either only be open to members, or members get a bonus.
We'll like you more.

I guess the real question is...why shouldn't you register?

Why yes it does.
The list of members is a little off in the forums, since it will only add users to that list if they actually go into the forums.
Just register on the front page, login, and you're good to go.

There could be a couple of reasons:
1. Make sure you're caps lock is off. I know, we've all done it. Passwords are case sensitive.
2. Clean out your cookies. Once in a while some bad cookie (probably something with raisins) will cause you not to be able to log in.
3. Use the 'resend password' link.
4. If all else fails, send the webmaster an email describing the problem.

That's what the "add a question" link is for at the top (viewable by registered members).