Deep breath:
You remember when you used a stand alone Word Processor and a stand alone Spreadsheet, and couldn't cut and paste between the two.
You remember getting excited about managing to free up more than 600k of your 640k low level memory.
You remember when "Performance Enhancement" meant tweaking your autoexec.bat and config.sys.
You remember when you owned programs that didn't support a mouse.
You remember when XTree Gold was a valid alternative to MS Windows 2.
You remember when you booted into the DOS Command Shell.
You remember when you had to manually copy device drivers from a floppy to your hard drive and add the appropriate line to your config.sys.
You remember when you had to manually copy device drivers from a floppy to your boot floppy and add the appropriate line to your config.sys.
You remember when you didn't need device drivers.
You remember buying the original 8-bit AdLib card, with it's single 3.5mm jack plug and 2 inch long volume knob.
You remember the 3Dfx Voodoo vs. Pyramid 3D debate.
You remember buying an EGA graphics video adaptor.
You remember buying aCGA graphics video adaptor.
You remember buying a text mode only video adaptor.
You remember the cheap Far Eastern Apple-II clones.
You remember the debate about 720k 3.5" floppies vs. 1.2MB 5.25" floppies.
You remember when you could choose between the non-IDE 1x Mitsumi 'drawer' CD-ROM drive, the 1x 'tray' Sony and the 1x 'caddy' Panasonic drive, and that was it.
You remember Sound cards that featured all three interfaces plus IDE.
You remember when software didn't have serial numbers.
You remember when games didn't need the CD in the drive to work.
You remember when games came on multiple floppy disks.
You remember when games came on one floppy disk.
You remember when you envied the guys with 24-pin dot maxtrix printers because you only had a nine-pin.
You remember when you could buy the game on CD with voices and CD music, or the floppy disk version with subtitles and MIDI music.
You remember when portable mass storage meant a 44MB Bernoulli 'Toaster' Drive.
You remember the MCA vs. EISA vs. VESA debate.
You remember MFM hard drives.
You remember when you could have a working PC without any Microsoft Products installed at all.
You remember DR-DOS, OS/2, OS/2 Warp and PC-DOS. (See above.)
You you can hold a conversation on what an "Altair" is without using the words "Abduction", "Greys" or "Anal Probe".
You remember when motherboards didn't come with disk drive controllers or ports build onto them.
You remember the 60Mhz Socket-4 Pentium.
You remember paying your ISP for your subscription, the time you spent online (by the minute) and paying for the cost of the call.
You remember when Mosaic was still a popular browser.
You remember when every CD-ROM drive came bundled with "Day of the Tentecle", "Return to Monkey Island" or "Myst".
You remember CIX. (UK peeps only.)
You remember when being a Compuserve user was fashionable.
You had a copy of the DOS version of PK Zip.
You had a registered copy of the DOS version of PK Zip.
You had a registered copy of the DOS version of PK Zip that you paid for.
You remember when license agreements consisted of a sticker on the disk saying "Piracy is bad, m'kay?"
You remember when Digital was Digital Research.
You remember when Digital was Digital Electronics Corporation.
You remember when Digital was Digital Intergalactic. (Really)
I can think of loads more, but I appear to have developed RSI whilst writing this, so I'm going to stop.
P.S. I still can't believe they didn't call the OpenGL version of Doom "GLoom".