New Demo:

https://www.gog.com/en/game/slavicpunk_oldtimer_demo

New Prologue:

https://www.gog.com/en/game/legendary_hoplite_ajaxs_trial

New Demo:

https://www.gog.com/en/game/trepang2_demo

New Prologue:

https://www.gog.com/en/game/don_duality_initiation

New Demo:

https://www.gog.com/en/game/laysara_summit_kingdom_demo

New Demo:

https://www.gog.com/game/masterplan_tycoon_demo

New Demo:

https://www.gog.com/en/game/tailquest_defense_demo

New Demo:

https://www.gog.com/en/game/below_the_stone_demo

Me likewise, though on occasion there was a free game too or some good software and mods (maps, levels, etc).

Hell I used to buy these cardboard sleeves from the Newsagent that featured almost nothing but demos in a specific genre. There was a whole series of those at one stage many years ago. And it wasn't just a genre, sometimes it was a specific game series. For instance one of them was based on Quake. I forget, but some of them possibly included bonus stuff like mods in an Extras folder of the disc.

EDIT
Just now I tried to find an image of such a cardboard sleeve with demos, and failed. They came out weekly or fortnightly I think, with at least a dozen all up, maybe more. Not seen anything like them before or since. They well tall (or long if you like), slightly wider than a CD. The piece of cardboard was folded in half like a book or folder. You had a fancy cover on the front with images of what you were getting, and the back was a blurb of general specifics and more pics. Inside on the left side was some descriptive stuff etc, while on the right were the CDs fitted into slots in the cardboard. It was all fairly high quality for what it was. You had a least one CD, usually two, sometimes three I seem to recall. Imagine two CD cases width wise on top of one another edge wise, that's how tall and wide approximately. I recall they were either done by PC Powerplay or PC Gamer or both. I have mine in a shoe box somewhere, due to their length. That shoe box is almost full with them, and I just tried to find it, and take a photo ... but no luck ... buried somewhere in my back room, which is cluttered with crap right now ... the price you pay for having kids and letting them come back home after moving out and collecting their own furniture and junk etc. Even my sizable shed is half full of their stuff. And one of my kids has a child, so a good portion of my home is taken over by them.

EDIT 2
Sometimes life can be truly uncanny.
I was at the Internet Archive, looking for a download link for Operation Wolfenstein, a free game at Itch.io where the current download link doesn't work, and while browsing I happened to see what looks like the back of one of those cardboard sleeves I mentioned above.

PC PowerPlay 40 Ultimate Game Collection

When to expect new demos?

analiticos of lastos tenos demos

Posted May 26, 2023 Friday

Posted May 30, 2023 Tuesday

Posted May 30, 2023 Tuesday

Posted June 21, 2023 Wednesday

Posted July 03, 2023 Monday

Posted July 05, 2023 Wednesday

Posted July 14, 2023 Friday

Posted 4 days ago Tuesday

Posted 3 days ago Wednesday 1 PM UTC like most demos (no demos on Weekends and Thursdays?

Posted 3 days ago Wednesday Most demos on Tuesdays and Wednesdays

Erbello`s timing is usually 1-8mins after the demo web address exists, hope you are all well GOG! ^
Welcome back : )

We Are Not Alone Demo is available on GOG now.

Typhon: Bot vs Bot Demo is available on GOG now.

Unsure when, but "Blade of Darkness Demo" is delisted.

https://www.gog.com/game/blade_of_darkness_demo
https://web.archive.org/web/20230127055255/www.gog.com/game/blade_of_darkness_demo

Gogdb says the price is not defined since March.

From the same source, there is also pictures of the front of the cardboard sleeve and the CD itself:
Front
CD
The price tag says: "$3,00 AUD" and "Mooroopna authorised newsagency"