I have no idea if Ayron's site was the source, but that was my only real download yesterday.

On doing my usual paranoid shut-down, Intelliscan by PC Doctor reported 2 instances of
"Trojan Horse: QQhelper.exe".

Clean-up went ok and warned me that on re-boot a full scan would ensue to make sure there were no other infections.

Full Scan took "a lot longer".... and reported yet another single instance of the same Trojan..... clean-up went, etc.... with the resulting required Full Scan taking even longer....

Aside from losing some recent work, I should have erased the drive and restored a backup.