Writer's block? Sometimes I just give into it! Take a break from writing.
I love the book THE ARTIST'S WAY by Julia Cameron. She recommends that writers go out and experience something totally new at least one hour a week. For example, spend an hour trying to play a harmonica, take a salsa lesson, go to a woodworking shop, or do anything that's totally new to you. I've used this trick before and find that after a breather and exposure to new stimuli, for some reason my brain kicks back in and is ready to write.
Another trick I use sometimes is to turn away from the project I'm stuck on and work on a different project for a while.