Helio announced this morning a hybrid card that supports both 3G and WiFi. The Helio Hybrid card and Hybrid Connector software are free with a two year membership costing $85 per month. It will be able to connect to the Internet via EV-DO or Helio WiFI hotspots.
As far as I know, Helio will be the first MVNO to offer a wireless broadband card. I'm sure this signals something significant, but I can't quite place my finger on what. Unfortunately, it also seems that this card only supports PC.