This may take me a while....
(in no particular order...)

PC1 - Linux Firewall (between internet and LAN).
P1-133 (leet!), 48mb ram, probably about a 1gb h/d).

PC2 - Mail server (windows server)
P3-600, 128mb ram, 6gb OS partition, about 40GB for Mail.

PC3 - DVD Converter (windows).
AMD Duron 850, 512mb ram, about 750gb h/d.

PC4 - Webserver (windows).
P3-800, 128mb ram, 20gb h/d.

PC5 - XDCC box (windows).
AMD Athlon 800, 768mb Ram, 500gb h/d.

PC6 - Torrent box (linux).
AMD (Athlon I think) 750, 512mb ram, 60gb h/d

PC7 - Radio broadcaster (windows).
AMD Duron 800, 384mb ram, 300gb h/d.

PC8 - FTP Server (windows).
P1-166, 48mb ram, 2gb h/d.

PC9 - Usenet (news) server (windows)
P2-450, 128mb ram, 4gb h/d.

PC10 - backup server (novell netware).
P3-800, 256mb ram, 6gb h/d running an ultrium LTO-3.

PC11 - backup server 2 (windows)
P1-200, 128mb ram, 4gb h/d running an onstream ADR30.

PC12 - HTPC (windows).
AMD Athlon 1200, 256mb ram, 40gb h/d.
This is just a test box which is testing out a custom front end/server with thin client support.

PC13 - Other half's pc (windows).
AMD AthlonXP 1800, 512mb ram, 40gb h/d

PC14 - Unreal Tournament (GOTY) pc (windows).
AMD AthlonXP 1800, 512mb ram, 40gb h/d.
I'm running a 2100dpi mouse with icemat (glass) mouse mat and teflon feet for a nice smooth gaming effect.

PC15 - M.A.M.E. PC (inside a 4player custom built arcade cabinet) (windows).
AMD AthlonXP 2000, 768mb ram, 120gb h/d.
This has a multiple effect front end, running full current MAME set, plus Daphne, vpinmame and various other emulators.

PC16 - V.O.I.P. / Fax Machine (windows).
P3-600, 128mb ram, 6.4gb h/d

PC17 - Firewall 2 (between external wireless and lan).
P1-133, 48mb ram, 2gb h/d.

PC18 - Webserver (apache/mysql/php/etc) (linux).
P3-600, 128mb ram, 20gb h/d.

PC19 - HTPC - Shuttle (windows).
Soltek Qbic EQ3702M.
XP2500+, 512mb ram, 250gb h/d.

Laptop1 - Main use laptop (windows).
P3-1133, 384mb ram, 30gb h/d

Laptop2 - Failover (windows)
P2-266, 192mb ram, 20gb h/d.

Laptop3 - Client pc (windows).
P1-166 64mb ram, 2gb h/d

Laptop4 - Client pc (windows).
P1-166 48mb ram, 2gb h/d

Laptop5 - Client pc (windows).
P1-166 48mb ram, 2gb h/d

PDA1 - Thin client for HTPC / Sat Nav (PPC2003).
HP Ipaq H5555, 400mhz cpu, 64mb onboard, 512mb mmc.

NAS1 - Storage (linux - debian + samba).
P3-500, 128mb ram, 2TB h/d.

NAS2 - Storage (linux - naslite smb).
P2-450, 128mb ram, 1TB h/d.

Most pc's are connected to my 48port switch, others are wireless.
All laptops/pda are wireless.

I have got other client pc's, but they're not used as much.

None of my pc's are an "impressive" spec (compared to the ones posted above)... but the combined spec doesn't work out too bad

I just need to build my new shuttle as a full HTPC/multi zone audio doobrey-firkin...

Just waiting to upgrade (20th october) to my nice new whizzy ADSL2/2+ service (24mbit).


EDIT: Missed off PC18...