What's your best tech purchase?

Over the years I bet we've all amassed massive amounts of tech, whats the best purchase you've made?

I would say my best purchase is my GTX 570. Geforce_gtx_570_3qtr_1000x580_gallery_preview_medium

via www.geforce.com

I love gaming and and when I built my new PC 2 years ago I had to cut cost on a component (I choose highest available parts at the time) and I choose to cut costs on the easiest component to upgrade: the GPU. So I got a placeholder Nvidia GT 240. For the next few months I planned on getting a GTX 470. School got heavy so I decided to wait as it would be pointless to buy with no time to play. A few months pass by and I change to getting a GTX 560 Ti. As I log on newegg to buy the GTX 560 Ti I see a Galaxy GTX 570 1gb (my GT 240 was made by Galaxy too) on sale for $340. Since then I've enjoyed the 570 by a random stroke of luck!