Currently in my hosting setup I have:
Cisco Pix 515 Firewall (1U, 64mb, VPN+, Additional FastEthernet, PIXOS 8.0(3))
Cisco WS-C3524-XL-EN Switch (1U, 24port 10/100)
Generic UltraSPARC AXe Server (1U, UltraSPARC IIi 300MHz, 384Mb, 20gb, 5x FastEthernet, OpenBSD)
From a networking/security PoV this is quite awesome. The server however is pants. It runs. But it runs slowly. So I have bought 2 more slow servers :)
2x Cobalt RAQ 3i (1U, AMD K6-II 300, 256mb, 20Gb)
I will upgrading these to the latest Strongbolt 2 distribution following a few tweaks (incl a dangerous ROM upgrade!)
One of the Cobalts will go into my hosting setup and the other will end up at home to replace my existing SME Server as with Strongbolt it can run SAMBA and process all my email and home web serving needs (with a 500Gb USB drive attached). These RAQs are low power and almost silent.
Also in my sights is a 1U NAS box - a Quantum SNAP m4100 - capable of running 4x 120Gb as either RAID 0, RAID 1, RAID 5 or JBOD. Plenty of space for storing websites stuff and such (esp. setup as a 360Gb RAID 5 array).
The UltraSPARC will then be retired for a Xeon or P4 based Dell PowerEdge or HP DL360 1U server. Both will be capable of accessing the SNAP server - which will be quite cool. A nice place to store all my MP3s and my huge mySQL databases.
Tried and tested. I don't need cutting edge for 95% of my stuff - but I do need silence in my lounge :)