Someone really should open up a Pageplus reseller store that accepts BTC. They have a pretty cheap reseller package from the company and I think it is about the cheapest phone service you can get right now ($80 credit with 1 year activation and $0.08 per minute using the Verizon network). I found this website
http://www.itradebtc.com/index.php?route=product/category&path=72_116 but I have not used them before and they don't sell the $80 voucher.
You could always buy ebay or amazon vouchers off bitmit and use them to buy the prepaid service of your choice.