I have done banner ads in practically every category, from Fortune 500 companies to mom-&-pop shops. Energy, Banks, Games, Food, Jewelry, Technology, Beauty, Military, Pets, Presidents and Paupers. Here are some of the ones I like.

Client: Obama for America '08

Campaign: Don't Get Mad

Al Designs: + Animation + Concept Development + Design + Illustration + Modified Content for CTR + Scripting

Sizes: + 300x250

Project notes: Generally banners are used to get people to do something on a website–the genius of this banner was that it was made for the sole purpose of collecting reactions. The banners touched on, health care, the Iraq war, gas prices, the economy, social security, and political process.