Just discovered this today. Kind of neat. It takes what ever URL you give it and makes a shorter URL that goes to the same place. So, instead of
You would have:
Which you'll notice leads to the same place. It's really handy for longer URLs. Let's say I wanted to link to a specific post in a thread:
Instead I would only have to link to:
Which, again, lead to exactly the same place. Cool huh?