Hi!
The new version of my AnyDice service just entered beta, and I'd love it if some people fooled around with it. It's an online dice probability calculator that can do a lot of stuff.
It's over at anydice.com (http://anydice.com). I'm trying to eliminate as much bugs, glaring omissions, and confusing bits as possible before replacing the old AnyDice service.
In case you already fooled around with the alpha, the biggest change is that rolled dice are now ordered from highest to lowest by default, but you can change this.
The most glaring omission right now is that you're not able to link to your results. That's the next thing I'll add.