Preserve variables between page loads?

This may have crossed the list a bazillion times, but I couldn't really find anything appropriate in the archives... maybe I just didn't look hard enough. In a MySQL app, I have the usual row of paging links at the bottom of the page and need to pass to the next iteration more variables than I can comfortably url-encode in the hyperlink. If all these paging links were submit buttons I could pass anything I wanted in hidden form fields, but since they're hyperlinks I don't seem to have that option. Is there a way to selectively preserve variables between iterations? Something like variables that are global to PHP, as opposed to being global within the script?