Good news - there might be a "Day of Unity" coming to a city near you!
Unity and Microsoft are running free day-long events aimed at helping you write Unity games on Windows devices. Did I mention it's free?
Just register and then turn up with your laptop (Windows or - gasp - Mac) and you'll get all the help you need to port your game or write a new one from scratch.
There are events all over the US in April and May, and also happenings in China and UK.
Link: Day of Unity
Update: I attended this day, and it was great. Came away with the ability to write many different 2D games in Unity. I see today there is an update to Unity published - version 4.5 - which polishes a few 2D issues.
If you are interested in cross-platform game development, Unity is an excellent tool. You would be amazed how much you can write without using C#, and when you do start using C#, it gets even better.