Did you know, that you can delete your own posts, or even threads?
It's as easy as 1...2...3.
1) While posting, you need to set a password to be able to delete your post or thread later.
2) See that checkbox next to each post and thread? To delete your post or thread, you need to check that.
3) After you checked the box, you can enter your password from before at the very bottom of the page.
There is another checkbox named "File only". If you check that one, your post will remain, but any file will be deleted.
If you do not check that, the whole post or thread will be gone, after you hit the "Submit" button.
That's it.

No more typos, accidental posts and so forth. You have control over what you do here.
Awesome, is it not?