Ask HN: What to do about laptop batteries?

I use my laptops so much that I wear out the batteries about once every year. (I have a Dell and HP, but this was also a problem with a Macbook.) OEM replacements tend to cost in the $100 - $150 range -- which is ridiculous considering that decent laptops themselves are in the $500 - $1000 range these days.

It's clear that manufacturers have figured out that they can pretty much get us to fork over an extra 10% of the laptop's cost for every year we use it.

So I've tried purchasing knockoff replacements from different places and have only been successful 25% of the time. Three out of four batteries died after a month. (And by died, I mean they suddenly went from powering my laptop for 4 hours to causing it to shutdown suddenly after 45 minutes.)

My question is this: What does everyone else do when their laptop battery dies? Do you buy a new OEM replacement, or do you have a goods source for cheaper reliable replacements? Does it make sense to pay for the extended battery warranty?

Also, I've seen this post on HN about repairing the batteries yourself, but the risk of explosion or fire isn't something I like to worry about: http://news.ycombinator.com/item?id=1403726