This guy has made some fun and clever stuff. Short and simple, mostly:

http://www.kloonigames.com/blog/

Not sure if that's what you're looking for, but there are some good 5-15 minute games in there.

I used it for a couple years. It was very handy

Didn't the original Heroes of Might & Magic go to the status of abandonware?

JFK Reloaded and mods.

8-Bit Killer andLocomalito's other games. All freeware and awesome beyond comprehension.

Do IP or copyright expires for games in general?. Is it at that point they effectively become "free" much like when copyright expires for books etc? (isnt there a 50 year maximum rule ?)

Nethack one of the best original roguelikes..and free :D

each country have different laws, but generally the same the same rules apply to games as other creative products.

The Clue!

https://sourceforge.net/projects/cosp/

Fantastic game!

Heroine's Quest is a fantastic hybrid puzzle/adventure game which is as good as the Quest for Glory series it was inspired by.

lol you're right. I didn't realize it was here all the way back.

not entirely true - copyright expiration is not hand in hand with "public domain". in certain territories (for example) while the copyright of the original holder may expire (an / or that of their estate), there is a re-appliction period to prevent others from misusing it or using it for profit (as many public domain works already are), but also to prevent corporate misuse (such as with the works of R.E Howard in that last Conan film - unfortunately both he and the film were US produced, so fuck-all could be done).
Source: Copyright lawyers fear me.

A freeware games list is meaningless if Iji isn't included.

PLAY IJI!

Would also recommend Rabbit Rush (I love it).

Thanks for pointing there! I think I fell in love with the trailer of Hydorah... Triggers cozy memories: R-Type, Katakis, X/Z-Out, Apidya, Project-X...


On topic: If someone is in for some really brilliant crazy shit, Jeff Minter has made Llamatron (2112) and Revenge of the Mutant Camels freeware in 1997. Unfortunately there is no official download site, so please ask the search engine of your choice.