Amazon is in general frowned upon here because of their ridiculous One-Click-Shopping-Patent. This should not keep you from posting links to Amazon on your homenode though - but you might want to consider asking vroom about his FatBrain account instead if you want to generate some income for him instead.

I don't know how he finances Perl Monks, but I imagine that some money will always be welcomed by him, as he's just a lowly student :-).