Virgin Mobile's just announced a prepaid 3G service under the Broadband2Go moniker, which will offer customers a contract-free internet option. The Novatel MC760 USB dongle -- which will be available exclusively at Best Buy -- will run $150, with fixed data rates of $10 for 100MB, $20 for 250MB, $40 for 600MB and $60 for 1GB. The $10 bundles will expire ten days after purchase, while the rest of them will expire after 30 days. Virgin's Broadband2Go will operate on Sprint's network in conjunction with Novatel Wireless. It's a tiny bit pricey if you ask us, but then -- most things with no strings attached are, right? The new service will be available starting late June.[Via