- By keeping the pw database in a Dropbox folder, along with a standalone version of keepass itself. No need to ever install. - By using a phone version of keepass to access the Dropbox pw database, thus always ensuring access to passwords. - In emergency situations, by downloading the above-mentioned db and software through the dropbox website, ready to use on any machine.
(all of the above are made more difficult by the switch of 2.x series to .Net, a switch without a good reason, too, so caveat emptor etc. Keepass once looked like a great project but this dichotomy is a disaster.)