I personally use KeePass, which isn't cloud-based, but I drop the database file into my Dropbox. I also have a copy of KeePass portable and my database on a disk-on-key which I keep on my keychain. This isn't usually up-to-date, but it does have the most important stuff in there.

I wrote a bit about KeePass and various tricks here, if you're interested: http://www.loopycode.com/solving-sign-up-anxiety/.

I think that Firefox, or any good browser with a sync feature, can be a good password manager.

LastPass is fantastic (http://lastpass.com/) for website passwords, but isn't too great for non-websites. It's very similar to 1Password, but cross-platform. It can be used to manage non-web passwords, but it's kind of a manual process using their secure notes.

I use Bruce Schneier's advice and keep them on a piece of paper in my wallet. Always safe and available. Of course, I only have a few dozen, not the hundreds some people claim they have to manage.

1Password from AgileWeb Solutions: http://agilewebsolutions.com/onepassword

And then sync the data in the cloud with dropbox: http://help.agile.ws/1Password3/cloud_syncing_with_dropbox.h...

1Password is integrated in the browser using a plugin (mainly safari under OS X, where it started, but I use it with Chrome with no problem).

Highly recommended

PasswordSafe on a dropbox shared folder works great: http://passwordsafe.sourceforge.net/

I use pwsafe over ssh on a remote host. Not decent but one option.

I use KeyPassX on Dropbox. It works, kind of.