Why does this happen?

[bllott]

The PR on my sites changes.. sometimes it shows as 4 others as 5, and sometimes as 1 or 0. Is it normal to have this flux? Or is it because my browser is fuckd?

[kostas]

Your PR is different for every SE. Also different is for every page in your site.Normally PR changes when SE robots check and index your pages.( Not so often). If it changes frequently without a known reason there is a problem.
A common problem may be the tool you use to check your PR. Try this:
http://rankwhere.com/google-page-rank.php?
I assume you do not confuse PR and results page position.

[Wiggles]

apparantly PR has been switching around today, odd since update was last week.