Simple: I haven't had to change it yet.
The mouse I'm using takes one battery and it's a power saver. That one battery lasts 12 months according to HP's site.
Also, I use rechargeable batteries, so I don't have to fork out any money to buy new ones.
I'm happy with the cheap wireless mouse I have (HP X3500). It's comfy and awesome.
I had a Corsair Raptor M30 gaming mouse, but I just didn't like it...
I only got one hair from it, and it fell off. Does that still count?
Pfft. You just need some more cheese.
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In boring news, I added another short film to my IMDb page.
I usually wait until December, even though I know that Christmas songs are gonna start playing on the radio very soon.
I didn't have any plans to go out this year, so I spent the night in bed.
It's still early days, so I can expect some level of disappointment. I felt the same with Matt Smith when he started up, but he steadily became a favorite.