Whenever I look at that machine I wonder if Sony really, really wanted to use the SpiderMan / PlayStation 3 font on the keys - it came out in the same year as the PS3, and Sony was mad keen on co-branding - but someone with taste and sense decided that it would have been naff, and yet he or she only managed to tone the font down a bit.
Was there any way to put a Pentium M in the Mac Mini? From what I remember the Pentium M and Core CPUs used a similar socket but were incompatible, but perhaps there was an adapter. The slowest Pentium M was 900mhz.