http://www.gog.com/en/forum/general/the_official_back_in_my_day_thread

Both those give me a headache thinking about them!
Phew! OK, it's been done, so I don't have to go there... :)

I know some of the older games actually had a physical device (decryption I think) that you had to plug into a parallel/serial port to get the game to run. That was some strange and OTT copy protection.

In the first realese Operation Flashpoint had increasing level diifficulity over the time of running the pirate version.... after a while player could be headshoted by npc shooting from other side of the island.

It was nowhere near as bad as it sounds. At least for the Amstrad CPC anyhow as that came with a monitor (either a greenscreen or colour one -- we had the greenscreen model as it was significantly cheaper).

I found one of the most weird and akward DRM was from the spectrum days with a thing called lenslock(think thats what you call it)Basically a piece of plastic that folds in 3 you put over the screen where a lot of blocks are shown looking through the lenslock you should be able to see 2 letters which you then input and the game would then run. Problem is 99% of the time what you see through the lenslok and what it was asking where two different things and it caused me headaches straining my eyes looking at it.

Ended up i could never play tomahawk as i could never read the 2 letters.

Original Pool of Radiance, and many other SSI D&D license games, relied heavily on the manual. You heard rumors and plot points, which were written only in the manual, so if you had a pirate copy you missed a lot of the game plot. Also they had the code wheel.

Similar stuff in Might & Magic 1&2 as well. You need to have the manual in order to know the spells you can cast, as the game doesn't show the spell names, you need to enter them by typing in their respective number.

Aah, good old times.

Wasteland would direct the player to a physical book for any significant amount of text. That could have been due in part to memory limitations. The order of passages was scrambled and there were several fake passages thrown in to confuse people trying to read ahead.

Mass Effect 1 had the star map disabled if it detected a cracked copy (that one got me to buy the game).
Beyond Good and Evil uninstalls the game just as the install has finished if the driver won't install (that one got me to buy the GOG version when I already had the game on disc).
Stardock's Windowblinds made the desktop black and gave the skins other oddities or disabled parts of them (this, and a reply on to another user on the support forum about it got me to buy the software 8 years ago or so).
... see, DRM works (hush, don't tell them).

There are more recent examples with USB sticks, probably not for games, but other software.

Dongles weren't so unusual for high-end software. For games, yes.

Can't leave out Crescent Hawk's Inception! Mild spoilers regarding the ending.
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After spending most of the game upgrading mechs and characters in a tactical combat RPG, the final sequence is a peaceful walk through an empty maze. Then you are presented with a huge map of the galaxy. You have to walk around bumping stars highlighted on a bundled physical map. Do it right and you win the game.

Odd and very anticlimactic place to put the copy protection.

http://en.wikipedia.org/wiki/Copy_protection#Notable_copy_protection_payloads

My favourite has to be, "On a copied version of the original PC version of Postal, as soon as the game was started the player character would immediately shoot himself in the head."

[raises hand]

That was me. I bought a something-something four pack of games, Settlers3 included. The iron was iron, to be sure, but the damn trees wouldn't grow after a certain point. Grrrr

Anyway, that was one that really confused and impressed me at the same time.

I hadn't thought about it in these terms, but you have a point. It was a clever design decision on their part ;).

Don't forget: If you want to improve sales, remove the copy protection!

http://www.scientificamerican.com/article.cfm?id=the-perils-of-copy-protection

I read that A Mind Forever Voyaging used a scratch-and-sniff coupon for some of its puzzles. Sounds pretty cool, but it sounds like a game like that wouldn't last more than a few years before the scents dissipated.