One of the bits of new code that went live recently was a feature that makes it easier to go to another user's full userinfo page.
In the search box at the top of most LiveJournal pages (in the Dystopia and Xcolibur schemes), typing in "exampleusername/full" rather than simply "exampleusername" will take you to that username's full userinfo page (http://www.livejournal.com/userinfo.bml?user=exampleusername&mode=full).
This is along the lines of the nifty fact that typing in "exampleusername/pics" takes you to the user's userpic page.