If you want something that runs android on wifi then check out the archos 5 its sort of the android version of the ipod touch.
keep your fingers crossed that something like the dell streak comes verizons way. all you need with that is a data plan. you can use google voice along with skype to replace the voice plan. $30 would be cheaper than a voice plan.
I have 2 lines on verizon. One is a droid with data and that's my daily driver. But I have another cheapo phone that is sort of a backup phone. I tend to use it when I'm using my droid as an internet connection for another device or when looking up stuff on the droid and want to have a conversation at the same time. The biggest reason that I would want a dataplanless android phone is for syncing my address book to this extra phone. The smoothest thing for me would likely be 2 fully activated android phones but I'm having a hard time justifying that extra expense. Somebody earlier in this thread said that a droid could be activated without data. Do we have confirmation of this from Verizon?
That said, it appears that when Verizon introduces tiered data, there is talk that a family share data plan will be offered as well.