Yeah. I've been thinking about how to best add more than one chain since I started. My main concern is making sure that at any time you can single click on a day with an unambiguous result (viz. it toggles color). So far I'm thinking some sort of tabbish view where you only see one chain at a time.

Adding non daily chains is something to think about.

Brett,

Here's a suggestion for non-daily chains: say I want to work out twice a week. I can set that property (somehow) in the chain name, and when I work out on Monday and market it on the calendar on Monday, it will have mon-wed marked off. Obviously, there's a problem with fractions, but it should work.

I've been using Apple iCal for chains!

Implement it like Apple's iCal. Have a menu at the right side where you can display, hide, pick color, add new chains etc. (chain is equivalent to subscribing to a new calendar in iCal). Can't beat the iCal usability.

Multiple chains concept sounds cool. In the shower this morning I thought of a dozen "chains" I want to start!