Each time I visit Helsinki, I try to get a room in the Crowne Plaza (http://www.crowneplaza-helsinki.fi/). First Class Service at reasonable price. All rooms have free internet access (wired). A small fee applies for wireless LAN. From the upper floors one can have a beautiful view over the finnish capital.
This tip has the address "Crowne Plaza Helsinki - Mannerheimintie 50 - 00260 Helsinki"