Just started on the Dell yesterday.
So far I've got 3 bright red LEDs shining down through the largish air vent at the front(above the USB/phone ports and below the dell badge). VERY nice- goes with the black/grey case perfectly.
Also threw in an old iMac 4GB hard drive to stick my music and video on- anyone know if one of these drives(Western Digital of some description) are fast enough to be worth putting the Windows page file/virtual memory on? Would that give a performance increase over just having VM on the main HD?
Anyway...back to hacks. My next idea is to replace all the LEDs with ones of a different colour. Was thinking blue for power, red for HD activity... suggestions?
After that, just basic mods like rounded IDE cables(preferably black or red), hard drive coolers, maybe a new fan up the front... unless someone here can give me some more fun ideas. 
Oh yeah- if anyone's wondering how to install a second hard drive in a Dimension 2400, it's easy- move the DVD/CDRW drive into the lower bay, stick the cover on the top bay(requires a bit of simple modification)and pop the hard drive on top of the CD drive. Use one screw to hold it in, and stick a bit of cardboard or whatever under the corners of the drive to keep it level. Does the job.
2nd hard drive bracket kit:
http://www.issue-resolved.com/
That thing: approx. AU$38.
Cardboard: Free.
The biggest performance increase you're likely to see is that experienced by removing that boat-anchor hard drive from your device chain and pitching it into the nearest wood chipper.
Those drives *at best* handle UDMA/33, (The iMac itself only uses the yet slower 16.6MB/sec mode, so count on Apple to have seriously underspec'ed the stock drive) and are slower then hell in all other respects.
I used one as a root drive for a linux server for a while, so I know of which I speak. The only saving grace was I had enough RAM in the system that once everything was up and running it pretty much ran from cache.
--Peace
Well i do plan on keeping it in there for dumping music etc on... are you sure having the VM on that won't help performance at all? I mean, it would mean windows wasn't having to swap files back and forth on the one drive all the time...
get a cheap fast HD of eBay or something ... those iMac drives, as eudi said, are slow slow slow ...
TOM
Ok ok I believe you now!
I've got it set so it's always switched off unless I open Media Player or go through its files.
A second HD isn't at the top of my list, given the 2.5GHz Celeron and 256MB RAM...
I'm now thinking of doing something involving paint- but can't work out what. Maybe red/orange flames on the round, recessed Dell logos on the sides...?
add a window, and maybe some LED fans!
after you add more ram though, 256mb these days isn't good for anything. and BTW most of the time you can find 40gb hdd's for $48 bucks, and thats if you get a nice one. :o
I thought of the window, which would mean replacing the side access door with a big perspex sheet(maybe held on with velcro or magnets etc.) but I don't have access to a bandsaw...
LED fans are a maybe... but I'm still unsure about having the wall behind the computer lit up
Well this is what happened to the poor dear today(;)).
I took out the original front vent lighting, removed 2 LEDs from the PCB and stuck them at the very bottom of the front inner panel shining downwards. Used the same USB port for power. So now we have a gorgeous, subtle red glow escaping from underneath- VERY cool.
I also went down to my local electronics shop and picked up a blue LED- DAMN THESE ARE EXPENSIVE! $0.35 for red, $8.95 for blue... yowzers!
Anyway this completes the status indicator LED changes: red for power, beautiful blue for HD access. When the blue LED really lights up, the upper front air vent gets slightly lit up which gives a nice lightning effect in the dark, but it's not nearly enough to bother you.
I'm really liking where this is going...
40 gigs=48 bucks?
200 gigs=90 bucks
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=423018&Sku=THD-2000JB%20P