Steven Combs has made an iPhone dock that lets him rotate his iPhone to utilize both portrait and landscape settings.  Also, the nifty dock is made out of LEGOs which makes the dock an awesome display of futuristic geek innovation and DIY motivation.

There are other docks out there which rotate so that you can use your iPhone in either display mode; however, taking a cue from Steven Combs and making your own will definitely be easier on your wallet.