One of the adds on Allakhazam targetted to the Dutch contains spyware. When browsing the site, I sometimes get a popup window asking if I want to do a disk test. If I try to cancel or close it, a new window comes asking me to install a "schijfbewaker" (disk guard) program, and tries to install an exe after a few seconds.
I've only had this happen when browsing Allakhazam, on several machines and while using Firefox. I might have seen a second version of it that used a different name as well, but I'm not completely sure of it.