I purchased the following laser pen of an eBay seller 2 months ago after searching high and low for a good cheap product, since the last one I purchased previously for my cat used the micro batteries that lasted 5 minutes.
This one is only £2.99 half the cost of the one i got from Petsathome and FOC Postage
The best thing is it uses 2 X AAA Batteries that last ages.
This has got to be my cat favourite toy at the minute!
See Link For Information -
Cat Laser Pen