On the seventh day of Christmas my true love gave to me...
Bluetooth Headphones
I can personally vouch for this gift idea. It's awesome. I have these. These are the Motorola S9-HD. If the nerd in your life uses a phone, mp3 player, or stereo with bluetooth capabilities, they've got to have this. They are stereo wireless headphones.
I use mine with my iPhone. I can get in the car, put them on, and have easy access to everything on my phone; music, podcasts, even phone calls. No need to ever take my hands off the wheel.Yes, I may look a little goofy wearing them, but the benefits are worth any goofy looks I might get.
You can also use them when doing more active activities than driving, but as you can imagine, mine are mostly used when driving.