I wouldn't lower or raise a Hummer. If you do, you risk a proportioning problem, making the rig look funny.

I think best function and best looks can be done with smart wheel/tire choices.

37" MTR tires make for a wicked off-road machine. They provide an inch of lift, which makes the H2 even more superior to the H1 in departure angle, and does a lot to catch the H1 an approach & breakover angles. Someone posted a really nice truck like this, I think it was in NJ of all places -- where does one off-road in NJ?!

If you're street only, you can do well with some nice rims and tires. For example, I think this white street H2 is /really/ well done: http://store.310motoring.com/image/s...er%20LARGE.jpg

Before you make any mod to your Hummer, think about it. A lot. Is it /really/ an improvement over stock? Is it going to be top quality? Is it in good taste? Hint: if your modification is done via double-stick tape, you need to get your head examined and you'd better have your wife check that your clothes match before you leave the house.

Street trucks /do/ make sense. The reality is street trucks are actually more practical than off-road trucks, like it or not. Even if you're a hardcore wheeler, you're most likely on pavement more often than not. Most off-roading is just for fun -- of no actual productive purpose beyond a sporting challenge.

Good taste and good sense can be had on road or off.