Bugbear is what seems to be similar to the Klez virus in that it seems to be able to send from it own STMP and take any email address as the sender, plus you do not even have to open the attachment to get infected so beware. We must have received a few hundred over the night and while NAV and NIS quarantine them they still come into your box with an attachment and all the subject lines seem to be different.
More info : [symantec.com...]
there is also another called opaserve but we are receiving a lot less of this one :
[symantec.com...]