For anyone interested in the iPhone cassette-style case, it's available cheaper here, and for 3G / 3GS, as well as iPhone 4:
http://www.perpetualkid.com/tuned-up-iphone-case.aspx
I'm not affiliated and have never purchased through this site, though. I bought my case (without stand) for about $3.50 USD in China. Note that the case doesn't have a cut-out for charging. For $3.50, I wasn't expecting much, lol.