Printers tend to fail. In my company, we had one that ended up making us mad with all sorts of failures (see next step), wasting a lot of paper. So I decided to transform it into something it could be very good at: a shredder.

Step 1: Printer Failures

Non-exhaustive list of possible printer failures that can drive you mad:

just won't print
stays stuck in the middle of a job
ejects a blank sheet before, after, or instead of your print job
will output lots of pages full of text with weird characters, instead of what you expect
PC Load letter syndrome (actually, could be your mistake, A4 vs Letter)
no more ink, in the middle of your 100 pages document
does not resume correctly (skips a page) after you had to reload paper in the middle of a document; very annoying when double-sided printing...
paper jam
after you fixed the paper jam, resumes printing but skips a page
loads two pages instead of one (inserts one blank page)
loads two pages instead of one, but slightly shifted (wastes two pages)
loads page with a skew
refuses to print a black/white document, because one of the color cartidges is empty (although there is enough black ink)
spreads ink/toner everywhere
folds the pages (unfortunately, not as a paper plane)
etc, etc, etc...

When you've decided it's time to get rid of it, you have several possibilities, among which:

do like in the Office Space movie
just dispose it calmly and properly
or, turn it into a shredder (and for me, apply to the Dead Computer Contest): Read on...

Step 2: Protagonists

The printer in question.

This one is a venerable Konica Minolta Magicolor 2350 color laser printer. It was certainly among the awesome ones, back in the days when color laser printer were uncommon, big, heavy (lots of parts were made of metal), slow, and very expensive (way more expensive than the toner -- unlike nowadays).

A small shredder.

Note how both styles differ. WALL-E and EVE ancestors?

Step 3: Rip the Guts Off

Remove all what can be removed without compromising the case stability.

You will end up with a big amount of waste. Similar to after eating artichokes.

Many parts are very specific and probably difficult to reuse, but some can be salvaged for future projects (motors, switches, magnets, and a crazy amount of screws).

Dispose the rest properly.

Step 4: Install the Shredder

I had to enlarge the paper ejection slot, to give access to the shredder.

Step 5: Use IT!

Well, it may look like a familiar scene, indistinguishable from a regular printer at first, but the paper now moves in the opposite direction!

Step 6: ShredDirect [TM]

One word about the ShredDirect [TM] technology.

How often did you notice, right after clicking the print button, and before it was even printed, that your work was not perfect enough? How many times did you print your work until perfect?

Now with ShredDirect, you waste the same amount of paper, but you save the ink!

Here is how it works:

Instead of printing your document, take (manually) a sheet of paper from the tray, and
shred it (see picture).
Improve your work on your computer, and repeat until fully satisfied. Only then, print for real.

Compatibility: ShredDirect works with most modern operating systems, and Plan9.