We have it in Sweden, too. I think you pay 50 kr (6 dollars) to look up somebody's declared income - anonymously.
There's a website for this: www.kollainkomst.se (check incomes)
If someone makes a request for your personal income and tax information in Sweden, you'll always get a letter with the name of who requested your information and a copy of the information that was supplied to them.
Presumably that is the raison d'etre for third-party companies offering anonymous lookups (of what is essentially freely available information) for a fee - whoever gets looked up receives notification that Leeches-R-Us, Inc. looked up their details.
Finland also. You can check people's tax rate and then quite easily make an accurate estimate of their salary based off that. I'm not aware of anywhere to look it up for free (offhand) but it's no more than 10e last time I heard.
