They also sell a 5W candle bulb (with a B22 base, which will fit in most light fittings - such as my desk lamp and many table lamps - even if they weren't designed for candle bulbs) for �2.99. That has an output equivalent to a 25W tungsten bulb. The web site doesn't mark them as 'web only' but I'm not very confident about whether my local branch of Maplins will have them in stock when I need one:
http://www.maplin.co.uk/module.aspx?ITAG=SPEC& ModuleNo=46267&doy=6m1#spec
I fail to see why anyone should be worried about the immediate
safety of a sealed unit just because it contains mercury. I accept that there might be concerns over re-cycling them but, if we're all going to start worrying about sealed units with mercury in them, there will be thousands of thermometers and barometers which will have to be disposed of.
Chris