I found this article about a new feature in Chromium that allows to use the Gnome Keyring or KDE Wallet as password store for Chromium. The article states that you need a nightly build for this, but as it is already a few months old I thought I’d try it with the Chromium Version shipped with Ubuntu 10.10. Turns out that version (in my case 7.0.517.44 (64615)) already supports the feature. Just edit your Applications menu entry for Chromium to pass the right parameter (right click on the Applications menu, choose “edit menus”, choose “Internet” on the left, “Chromium” on the right and then press the “Properties” button.). Edit it like this:
/usr/bin/chromium-browser --password-store=gnome %U
Now Chromium stores all passwords I save for webpages in the Gnome Keyring. Sweet!