I was researching some network equipment, looking at lots of websites and comparing products.
Then my desk phone rings. A call being passed from the switchboard - someone asking for the person responsible for IT purchasing.
It was a sales rep from a network equipment distributor, saying they noticed I was browsing their website and wanted to help me through the purchasing process.
I had never used their website in the past. No-one from my company had. I never signed up. I didn't login. I was bewildered.
I asked how they got my details. The rep said they pay a third party remarketing agency for contact details of people who visit their website.
We were a really small company, with no DNS PTR on our main (NAT'd) public IP. We did have an A-record for our mail domain pointing to this IP.
As the sales rep didn't know my name, all I can assume is that their remarketing agency was looking up our public IP addresses in some IP-to-business database, populated by email headers or sign ups at other user sites.
In any case, I wasn't pleased and was pretty surprised at the rather aggressive sales technique.