Airplane mode would sort of do that, but would also disable your phone as well. Why are you trying to do that? Maybe that would help us offer a better solution.
APNdroid from the market will do this. You can download both that and timerrific from the market and your droid will automatically change to whatever connection settings you like at different times of the day.
reason for me turning off my internet on my droid x
Hi folks the reason being for me is this. i have a reachout wireless phone plan tha runs on the VZW network. I had a page plus phone that I switched to a droid x. The problem with this is the phone data eats up the free min on the phone. So I turn off the data enabled switch and when i want to use the internet i just use my mytouch 4g save my min on the dx and just use the network to use the phone the best of both worlds for me. The phone itself will do it no apps needed hope this helps if not it helped me.