My trusty IBM PC/XT! 
This little gem helped me write many a term paper.
And about a million lines of code! Everything from a For Loop to a Skip List to a fuzzy Hopfield Neural Network. This little baby has been in the trenches and seen it all!

This is no clone. Oh no, only the real deal IBM IRON HERE!

Oh, and it's a screamer... Yeah, it has a super rare Microsoft Performance Enhancement Card called the MACH 10! It takes the original 4.77 Mhz 8088 processor out of the action and unleashes Hell's fury with a 9.54 blistering megahertz of 8086 processor power baby! Now you can play DOOM and Duke Nukem like a boss! (one of these new in the box recently sold on eBay for $650! http://www.ebay.com/itm/Vintage-New-Sealed-Microsoft-Mach-10-Performance-Enhancement-Board-For-IBM-PC-/292106371855?hash=item4402e5830f:g:KDUAAOSwuMZZC17I)

Oh, that's not enough testosterone for you Tim "the Toolman" Taylor? Well "Hawrr hawrrr hawwrrr!" it's got the 8087 Math Co-Processor too! Lotus 123 and an 8087 together? It's like pornography for accountants.

But you say, "That's a lot of horsepower but I want pretty graphics." Well she's got it in spades. Yeah that's right. She's got a Paradise EGA card and the real deal IBM EGA monitor as well so she's sporting 16 COLORS! (That's more than we dudes can see anyway!) More than enough to play Sim City until the wee hours or the morning (That was you Jack)

Wait... What's that sound? It's like a pissed off 20 pound bumble bee or something... No... That's an original IBM ProPrinter dot matrix pounding out its inken fury on some innocent piece of folding tractor feed paper! Yes, if you buy right now you also get this awesome printer that's guaranteed to wake your college roommate when you print off that 25 page term paper (double spaced) at 3 in the morning! (Sorry about that Nik!)

Trying to clean out the attic a little so grab it before I donate it to the Smithsonian!