Chances are (about 99.9999%) that you don't have access to the HTC Hero just yet, but that doesn't mean you can't run its famed HTC Sense Android skin.
According to some Italian software enthusiasts, it is possible to flash your G1 with their SuperHERO ROM, a port of the HTC Hero's firmware. Aside from the OS skin's beautiful graphics and animations, SuperHERO will activate G1 multitouch that allows you to zoom into webpages a la iPhone.
Of course, Bluetooth and Wi-Fi aren't all that functional with this firmware, and the OS can get a bit laggy and light on memory. So you'll need take the good with the bad should you decide to hack your G1. [HD Blog via androidguys]