This is the little kitchen timer I use. It lasts around 6 months or so before the battery starts to peter out and the numbers in the display don't display all that well. But it will still keep track of time and if I hold it just right I can see the numbers. Eventually it gets to the point that the battery should be replaced. Now the strange thing is, and why the post here on the blog, I can buy a new timer for half the price of a new battery. If anyone can explain that I'd be interested.
In case you ever wondered what the inside of one of these gadgets looks like.
I popped out the little magnet on the back and saved it. Might come in handy someday.