[henri]

I would love it if I could assign background colors to items, that could be used for sorting (as in Mail.app), filtering, and perhaps grouping. It would be like the flags, but would have the possibility of having many values, rather than just flagged/not flagged. Colored flags would also work, sort of like the colored stars in gmail. I'm not sure which is preferable, though I lean towards colored backgrounds.

How one could use these:

* A color for "Monday-Friday" (or its complement, "weekend"). This way I could not see weekend tasks during the week, or vice-versa. Useful for sabbath observance, say.

* A color for "volunteer work", which is not exactly work, but is also not exactly play.

* A color for "waiting for", to identify those items that can only be acted upon once one hears from a third party.

I'm sure other users would find other uses.