I have been thinking of using Roll20 for an online campaign. Has anyone used this? If you have what customizing did you do to make it work for Arcanis?

I use it all the time, it is an excellent platform. You can use it for free, or if you get a paid account there are perks.

I haven't found that any modifications have been necessary. Generally when we play we use a G+ Hangout for video/voice chat. You can do all of your dice rolling in Roll20, and set up macros for your rolls.

In the most recent patch they have introduced a character sheet (currently in beta, and only available to paid memberships), which is supposed to be customizable. When I get a chance I plan on looking at designing a character sheet for Arcanis characters.

I highly recommend Roll20. They have a couple videos you can watch on the site where they go over the features. If you can afford $5-10/month, I would suggest going with a paid account, the extras are worth it.

I meant Macros not modifications. I played with it some today. Any particular Macros you use? Would you want to share them?

I saw the thing about character sheets that would be outstanding if you created it for public use. You would be the man!!

Sure, here are a few I use:

Initiative [[3d10kl1]]

Basic Attack vs. Avoidance [[2d10+1d8!+3]]
Damage [[1d8+1d8!+1]]

Perception [[2d10+1d8!+3]]

Just change the coloured number to your stat/die. The exclamation mark denotes an exploding die.