I'm looking for a web-based to-do application with a few very specific features, but, essentially, one that's almost a del.icio.us clone and is very much centralized not on categories, but on tags.
I was hoofing my way around my Backpack account and realized that I had not gone through the majority of things in there. Basically, it was a hassle to find things and to read; 37 Signals makes nice things in some ways, but they've applied tagging to pages, not tasks, and there's a host of other imperfections and problems which make me realize I very much want to migrate, the gist of which is that it obviously just isn't effectively working for me if it's a pain in the ass to go through.
What I'd ideally like is something that's almost identical to the delicious interface, where I could use a bookmarklet to add a task. The nice things about tags is you can then proceed to set up your own system -- i.e., anything with a 'p5' category might be important, or I could tag "grocery" for grocery shopping, and then like delicious, you could join tags (i.e. http://del.icio.us/tags/tag1+tag2) to get more customized reports, i.e., http://hypotheticaltodolist.com/WCityMike/grocery+downtown or http://hypotheticaltodolist.com/WCityMike/grocery+nearhome.
There's not much use in public sharing of this data, so privacy would be nice. It would also be good to be able to encode HTML inside an entry, i.e., "Check out this website
and this website
tonight." But the absence of either of those is not a killer.
Remember the Milk is close to what I'd like, especially with its Smart Lists and tagging and search language, but even it is slightly more complex than I'd like in terms of data entry -- and I find the checkbox NOT representing a complete horribly counterintuitive. That having been said, I'm thinking I may migrate to a combination of a private Furl account for todo-related URLs and a Remember the Milk account ... but ideally, it'd be even nicer to go a different route with this and have them together in this dream app of mine.
I should say that the primary reason I'm looking for this in a web app is I'd like to be able to be able to access the data from Mac and Windows platforms at home and work, respectively, and perhaps even on a cell phone -- and web apps traditionally have that portability.