chalst is fighting the good fight against spam. A few months ago I contacted Adecco NZ's IT department after I noticed a spammer creating advogato accounts linking to Adecco NZ and Adecco Australia. I said:

I assume you have hired someone to do some seach engine optimisation, or try to improve your google ratings - if that's the case, you've hired a lowlife who is willing to abuse unrelated websites to post spam. If that was done on Adecco's behalf that's a great way to damage your image and to get a reputation as spammers.

They replied:

Thank you for deleting this account. This advertisement was not done on behalf of Adecco New Zealand.

We have had issues with a scammer [...]. This scammer has been posing as an Adecco New Zealand employee on international job forums and is luring job seekers in to a money forwarding scheme. We have notified authorities and are actively working to shut this scam operation down.

If there is any help you can give us (i.e. IP address/ISP this person connected from to your servers, etc), it would be much appreciated.

So apparently not all spam accounts are misguided attempts at SEO, some may be slightly sneakier.