We did it in 2004. DS has food allergies and DH was on Atkins, so we had some specialty food items I wasn't sure we would find easily, so I shipped a box of snacks, etc ahead. It cost about $20 to ship UPS ground (heavy box), but it was so worth it! We used up almost everything in the box, so I didn't have to worry about shipping anything home.
We attended a wedding at the beginning of our DL trip this summer, so I intended to ship home our formal clothes so that we wouldn't end up lugging them across the Southwest for 10 days.... well, DH didn't see the "need" for that, so we didn't ship them, but the trunk of the rental car was JAMMED for the entire trip and the kids and DH ended up having to keep stuff around their feet in the car (I was the sole driver). I wish he hadn't been so stubborn... it could have been a much more comfortable drive!...............P