Best Adsense for side bar

[ibaker]

I have the normal 250px wide sidebar on my site so I was just wondering what type of Adsense advert is best to use for the side bar...currently I am trialling a:
- 250 x 250 square
- text & image/rich media ads
- Show blank space

As you can see I am new to all this Adsense stuff and not sure how to get the best revenue whilst also making my site look good

 

[CTXMedia]

I use a 200 x 200 square as it allows for some padding space either side and you can wrap a bordered box around it and add a heading (if you wish to).

Have a look at the homepage to see how I've implemented it: www.cyclechat.net

Cheers,
Shaun