'Twas brillig, and the slithy toves did gyre and gimble in the wabe

The Ikea ones are actually relatively expensive at £20/pack, considering that you can get similar strips on eBay for quite a bit less (I went for the Ikea ones mainly because I happened to be there getting the rest of the new furniture). A friend bought a set a while back to fit in his living room.

I did consider getting RGB ones, but looking at them in the shop I decided that I preferred the white of the single-colour strips to the white of the RGB ones (the single-colour strips have a warmer colour).