I had my first one in 1998, a pentium 2 400mhz, ali chipset pc chips mobo (it sucked so bad!) 64mb ram (pc100), 6,4GB hard drive, 36x cd-rom, 15" crt monitor, mouse, keyboard and speakers.
By then it costed $2.000!
Then in 2001 bought some upgrades (athlon xp 1600+, epox w/via kt266a mobo, 256 ddr266, 30GB Hd, cd burner, geforce 5200) and used the same case and peripherals (included the poor 230W PSU). All that costed me about $700. Later upgraded the monitor with a 17" philips crt and geforce 6600gt. ($450 more)
Next step was in 2005, when I bought an used 21" Viewsonic crt monitor, an athlon64 3000+ (socket 939), nvidia chipset asus mobo, 2x512MB ddr400 ram, 250Gb WD HD, DVD burner, 450W PSU, Asus case, and a geforce 7900gt. About $900 this time. From here on, using my Philips music combo that has usb streaming, so great sound with no souncard needed!
My latest rig (2007) is an Athlon x2 6400+, 6 gig ram ddr2 800, asus mobo w/ amd770/sb600 chipset, 500GB WD HD, Geforce 8800gt, Lg DVD-ram, Antec 550W PSU. (All for $1.000)
In november 2008 got my lovely 27" LCD Dell 2009W ($1.000), wich I enjoy very much using (gaming, movies, web surfing, everything!). And that's the most costly single piece of hardware I've ever own... So far. I wouldn't bet on it being the last one, for instance, I'm looking forward to buy a 13" aluminum Apple Macbook that'll set me back some $1.300 or more... Crazy race, ain't it? Sometimes I wonder what will be available in 10 years or so... Can U imagine that?