Ask HN: How do I convince my boss that he should get me a Mac?

I've been working as a web developer (client and server) at this company for over a year now, and the office is full of PC computers running either Windows or Linux (programmers may choose themselves). The thing is I am a Mac user, and a quite devoted one. I dislike working in Windows as I feel the means for increased productivity in Windows are far behind the thought-through UI and apps of OS X that help me get my daily work done. Also, Linux is not an option as---as extremely impressing as it might be---it is (honestly) a bit shaky on the desktop.

IMHO, the best of both worlds is OS X with its glitch-free UI, stable core and BSD roots with a terminal and toolset similar to the one in Linux (a great aid for us developers developing for and working with Linux servers).

So, what I want to do is to try and convice my boss that he should get a Mac for me the next time it is time to get some new hardware for the developers. How would you go about doing this, seeing as Macs are a bit more expensive than a bundle of workstations from say Dell?