Another excellent post by Scott Hanselman about shit we web programmers do that mess up the way people interact with the internet.

http://www.hanselman.com/blog/StopDoingInternetWrong.aspx

My personal favorites in this list are the giant Interstitial ads, not linking labels to inputs, and the banner that asks you to install the ad (that's actually a "feature" of Mobile iOS). The giant image thing is annoying as well but not something I usually notice on a high speed connection. I actually had a project I took over once where someone used three 2 MB pictures (not much now I know) and the client was confused on why the page loaded so slowly...