There are many many many cell phone plans out there. One of the best offered is boost mobile, which uses sprint towers but is a NO CONTRACT cell phone service which offers a Completely Unlimited Plan; Talk, Text, Web.
Now Boost Mobile is making there service even better by offering 4G compatible phones! The two phones they have available now are the HTC EVO Design 4G and The Samsung Galaxy S II 4G. The Best part is no matter what phone you have the Unlimited Plan is just $50 a month. So can anyone say UNLIMITED 4G!!! Here are links to the two phones over at the official boost mobile website.
Here is a Link to Both the phones, The HTC is similar to the HTC for sprint, and the Galaxy Comes in Black or White. If your looking for a 4G phone with an unlimited plan, look no further, Boost Mobile has some pretty good options for you.