For a limited time,
of free talk time added to the next billing cycle. Share with anyone you know that has Nextel. Might work for Sprint too. I got my email confirmation in 24 hours.
http://www.mynextelbonus.com/Registration.aspxAs far as Boost goes, I tried it and I did get a conformation but I'm not sure how they would add anything to a pre-pay account since it doesn't have a monthly billing cycle.