I've been using something similar of my own making, and I've been meaning to clean it up and publish it at some point. Since I have enough side projects going that I have no idea when that will be, I'll share a couple features of mine that I think make it unique and which I think should be incorporated into the others.

The general concept I stole from somewhere else -- you've got a stored list of sites and when you type your master password in a field, each site in the list then gets a "copy password" button based on the site name + master password. But this isn't quite flexible enough for general use, so I added some features:

First, each site has a 'version' field which becomes just another piece of data input to the hash. This makes it so you can rotate passwords on a particular site without changing your master password: increment this number and you get a whole new password.

Second, each site has a password 'scheme' which allows for disparate password requirements on different sites. The underlying generation algorithm is the same, but rather than converting the hash output to a base64 number and using it directly, the hash output is used to deterministically select characters based on the rule set. Roughly, each scheme has an arbitrary number of character "classes" that may be included (e.g. "numbers", "letters", and "symbols") and each scheme may specify a minimum number of characters from each class (a typical rule being that that min=1 for numbers and symbols). So the class-specific minimums are satisfied, then the rest of the characters are selected from all classes equally, then a few more bytes of hash are consumed to deterministically change the order of the selected chars (otherwise you'd always end up with your minimum two special characters at the front, for example, which technically weakens the password). Each site also can have a distinct password length setting. Currently I only have three or four different "schemes" defined and haven't had the need to add one in a while so they're all hardcoded, but one could easily imagine having a "password scheme editor" which lets you define new ones with a few primitive rule types.

And third, each site has a "last changed" date which helps me keep on top of which site passwords haven't been rotated in a while. If you change your master password every time you need to roll one site's password, this probably isn't an issue for you, but I definitely prefer to avoid the ritual of changing passwords on every site I use at once.

My impetus for all the password scheme complexity is that I found that more straightforward password generators simply don't work on all sites, and I hated having exceptions. The site where I pay my electric bill, for example, doesn't allow exclamation points in passwords, and they must be between 6 and 8 characters. Lame to be sure, but I really have no choice but to go along, so my password generator must too.

All that said about my password generator, I think this is a fundamentally different approach to the problem and I think the cbcrypt approach is ultimately more interesting if we can get it incorporated into browsers. I've long thought we should expose some sort of modified SSH-agent functionality to the browser JS API so sites could do public key auth for login (with the appropriate user prompting, of course -- just allowing websites unfettered access to your SSH agent would obviously be a terrible idea).