With this Greasemonkey script, a popup with the mnemonics from this site is added to all Kanji on the answer and study side of the Japanese study site http://renshuu.org. This of course interferes with the normal functioning of the site but allows for easy and regular checking of the mnemonics of each kanji.
I created this and thisstylish script to change the colors of http://renshuu.org to a better suitable blue for long study.