Any way to extend Macbook Pro battery life?

Mine is always under 2 hours which is very short really. I've considered buying a second batter so I can swap it out when the first gets low. But has anyone heard of any special battery packs that can hold more power or anything?

http://forums.appleinsider.com/showthread.php?t=66063

http://www.batterygeek.net/

Sounds interesting thanks. I wonder how heavy they are to lug around? Also I wonder if I can get them in the UK (mind you I might as well wait until I'm in Canada and get one...)

Also I wonder if there are any replacement internal battery solutions that give more life?...

Not turning it on?

thats weird...my macBook pro battery last 3-4 hours with no problems at all..

I have a solid state hard drive in my current laptop and it really helps with battery life, I can squeeze up to 4 hours out of it sometimes.

Darkheart

Are you running BMax? I wonder if graphical apps run the power down...

im running Unity Pro..its 17'' Mac Book pro with nVidia 8800GT

Grey: power consumption of a hardware 3D adapter increases significanty when it's under load. Most laptops have attrocious battery life when used for actual gaming.

That's probably the issue as I'm using it for development when I'm mobile.