IKEA and Spike Jonze remind us above that you can't really hurt your old iPhone's feelings by upgrading to the latest, greatest iPhone 3G S, but that doesn't mean you have to dump the poor obsoleted fella either.
So what are your plans for your last-year's iPhone 3G or original iPhone 2G? Selling them on eBay? Unlocking them to use as travel devices? Keeping them as backup? Turning them into a dedicated couch-bound iTunes/Apple TV remote? Gifting them to a needy family member or friend? Saving them up to build the world's tallest iPhone tower? Sending them to Cellphones for Soldiers? What?