Entrecard.com is a great way to get some exposure to your blog. It's essentially free ad space, and your free to design your ad however you'd like. The designs are 125x125 and should also follow suit of your blog. (You'll read that a lot here) It's a good idea to have it as a permanent design, but if your like me every time you change your blogs design, you'll change your card too.
Here are some examples- click for full size:
Prices are $5.00 each or 3 for $10.00
