Use open-source tools such as SHA1-Pass. The passwords it generates can be recreated with openssl and any other standard crypto library.
Edit: I wrote SHA1-Pass, so I'm biased, but I know what you mean about having trust issues with closed-source password tools. That's one of the reasons I wrote it.
I use open source tools such as "pwgen", "emacs" and "gpg". Open up the encrypted file in the editor, type your pass phrase if you haven't this session, cut and paste, close file. The built-in keyboard navigability makes this faster than everything but the in-browser form filling.
You might consider renaming it. I've been looking for several minutes and can't find it via that name.
Is it this: http://manpages.ubuntu.com/manpages/natty/man1/sha1pass.1.ht... I don't see how you would use this the same way you'd use the other tools mentioned here. I can imagine a way, but it's no where near as convenient and still has it's own major usability problems.
Edit: I wrote SHA1-Pass, so I'm biased, but I know what you mean about having trust issues with closed-source password tools. That's one of the reasons I wrote it.