If you really don't need anything over the top when it comes to an iPhone case, you might check out these Ninja iSockits. These are obviously only going to be for those that find the sleeves to be nicer as far as protection goes.

All of their sleeves are made to hug your iPhone to keep it secure. The case will not only hold the iPhone 3G, but the original iPhone and the iPod Touch. If this plain blue doesn't satisfy your tastes, they have plenty other pattens and materials they use.

Each one is only $10 over at Etsy, which also means that you could pick up a few to suit your moods. They have everything from flower patterns, to plain, onto slightly more geeky designs. They also sell sleeves for MacBooks, if you'd like to get all of your gadgets in matching sleeves.