Been using camelcamelcamel.com for this. They have great FF and Chrome plugins that can display graphs of the price over time of products on amazon pages. Also can email alert you when price drops.

Doesn't work for Chromium 10 on Linux unfortunately

I'll look into this, maybe I can fix it.

How is this difference than http://www.pricepinx.com? I currently use this site and it tracks more stores than just Amazon.

Just an FYI: http://www.gazaro.com/ does something similar to this, and gives users scores on how good the deal is.

Ah cool, I didn't know about gazaro before.

I'm a huge fan of HN and with the constant reminders here of people successfully doing something, I've (re)launched an app that tracks amazon price drops. Thanks hackers! Also special thank you to Joshua McKenty of http://www.piston.cc who built the first version of this.

How often do you track changes? What software are you using to get the changes? Custom built?

We're aiming for 5 minute updates on items, and we are using the Amazon API.

I installed it, but it isn't coming up after the restart. I'm using Firefox 4.

Hmm... I just tried fresh FF4 and the settings window came up right away for me. Do you see "Buylater settings" in the Tools menu? If not can you email me your "Troubleshooting information" (under Help -> Troubleshooting information) to raph@buylatr.com? Sorry about that.

That'll last as your product list grows...

Does it apply to amazon.ca?

edit: just read the FAQ. Hope to see support soon.

do you run a cron job on your server scanning each price periodically for changes?

Scanning frequently for changes. We are aiming for 5 minute updates, but it depends on how many items are being tracked and if we saturate our Amazon API access.

sweeeet!