Hold my beer, as some might say... especially those that work at The Register. There is a nice piece written by Matthew Hughes in their 'Personal Tech' section on how to get started with a refurbished laptop of some sort or another running our favourite OS.
This is an alternative to the rampant consumerism the world+dog is fixated on and while I myself am partial to a bit of bling occasionally the resulting pile of e-waste I, like many others, hoard just in case can be a bit problematic. Use Matthew's guide as an inspiration and who knows what future greatness could await your precious offspring. If nothing else you can, as the byline says, enjoy the look on their wickle faces as they scream: 'Mum, what the heck is Linux?'