Through a lot of trial and error it is possible to switch it on. Open and close the lens cover vigorously and repetetively with one of the the batteries in the wrong way round.
But that gets a very annoying. So:
By taking it all apart, unscrewing things, and sort of aligning the shutter with the power switch that it is supposed to push about when moved (if you nudge it to the side and hold it in position with your finger, the camera will turn on - that's how you now it's the right thing), you can fix it permanently. I managed to work it out myself - it's fairly logical and straightforward, I hope. I wonder whether I 'suffered' one or two extremely minor electric shocks or something - really not sure what happened - so do be careful. Probably just some kind of moving part.
Now mine turns on as easily as it always did, but I made do with the arbitrary slightly ridiculous technique for several months.
joshuagoodwin.com
November 2009
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix digital cameras.