Visible.com - Unlimited Verizon service for $25 per month, best deal for lots of usage. This is with a group discount, but you can find random groups online to join. Each person pays their own bill, and the other users in your group can't see your full phone number so it is safe to use with strangers.
PagePlusCellular.com - Cheap cellular service for more limited usage.
This site is meant to be used as a reference for myself, although others may find it useful. I use it to keep track of certain fixes, software, and other solutions which I may need while assisting customers. The page layout is pure HTML/CSS and is kept simple to optimize loading time and fast results.