Bad script with lots of false positives. For .nl domains for instance, you must query it with whois and grep for "name.nl is free".<p>Just because there are no DNS records doesn't mean the domain is free.
I ran the script for a while and apparently these are available:<p>bjc.de
caw.de
cqk.de
ctf.de
eqn.de
fab.de
hwj.de
iwy.de
myd.de<p>I stopped it after that.