As well as giant cuddly microbes (http://www.giantmicrobes.com/), you can now get cuddly subatomic particles (http://www.particlezoo.net/)! My family often get giant microbes off me as they're adorable, cute and a nice random gift (my mum works for the NHS as a programmer and my brother is studying chemical engineering), but I think it's time to branch out in particles.
The perfect gift for the geek or even non-geek (they're so freaking cute!) in your life :D:D