I just discovered another solution, which is surely again a bit of an overkill, but it appears to be the most sophisticated one:
There's a 3G/WiFi-router called
Dovado UMR (
~ € 100 in Germany), that has two USB plugs. One is for a 3G-modem and on the other you can
attach a tellstick (~ € 70 including Europe-wide shipping
at temperatur.nu), which then allows switching
wireless power switches from multiple manufacturers (including Ikea) through web, SMS or a schedule. A bundle of 3 compatible power switches including remote control costs
€ 30 in Germany. Add a USB modem for € 30, and the total investment for enabling remote switch of up to 3 devices would amount to € 230.