I added a random level generator to my level editor for my game, Inertia. Just press G in the editor (but be sure not to overwrite something you were making). The generator spits out a level that is usually broken and unbeatable ('cause I suck) but nonetheless still interesting. That's why I shipped it, despite its bugs. It can help with writer's block, when you're looking at a blank level, to press G and start something to base your level on. I used this technique to create level 7.
The reason I didn't make it work better (because the deadline is still 2 days away) is that a) I don't want to look at that pile of spaghetti anymore, b) it seemed like it would be a lot of work for a game whose concept I'm kind of sick of, and c) I'm simultaneously doing Nanowrimo.
Check out my other projects too. I use procedural generation - or at least randomness - in basically all of my projects.