Thanks for the pointers on this one fellas.
I've checked out the Psyber Streaming Server and it doesn't look like it is the cause of my problems.
However I always say unless you are 100% certain, don't rule anything out. So needless to say I'll be keeping an eye out for this one.
I don't have any ICQ installed on my PC, so I think I can rule this one out, can't I?
Anyway I used the link petemcevoy provided and it looks like it's sourced somewhere in China.
I'll be keeping a record of the results produced, so if it happens again I'll know where to start.

Edited for updated info...

Just after I had posted my original reply my the results from a trace started at visualroute.visualware.co.uk came back.

Here is what it said..

inetnum: 210.51.226.240 - 210.51.226.255
netname: JINGYE-INTERNET-BAR
descr: Taizhou linhai Jingye Internet Bar.
descr: Taizhou,Zhejiang province
country: CN
admin-c: TC254-AP
tech-c: TC254-AP
mnt-by: MAINT-CN-ZM28
changed: [email protected] 20010918
source: APNIC

Bugger, bloody internet cafes, doncha just love 'em