My problem was DNS related - sometimes, anything related to donationcoder.com simply wouldn't resolve to an IP. If I added entries to my hosts file or used another DNS server (like OpenDNS), the site worked just perfect.
I don't know wtf the problem is, if it could be a misconfiguration at DC's end, or just my ISP (
www.cybercity.dk), or whatever - haven't experienced the problem with any other sites though.
EDIT: running a WHOIS on donationcoder.com:
Name Server: NS1.DONATIONCODER.COM
Name Server: NS2.DONATIONCODER.COM
Now, I'm a bit rusty at the more advanced DNS topics, but assuming that your (ISP or whatever) nameserver doesn't know about DONATIONCODER.COM, how will it resolve NS1 and NS2? Doesn't resolving NS1 and NS2 mean your DNS server has to contact
ns{1,2}.donationcoder.com, which it doesn't have the IPs for?