There are two, and I fear I can give good descriptions of neither.

(I hope.

)
Mystery game the first:
* Background: It was on an old (pre-iMac) Macintosh desktop computer.
* Year: I played it in the mid 1990s.
* Perspective: 2-dimensional, sort of tile-based.
* Art style: Very simple, but typical, I think, computer graphics for the time period.
* Environment: A grid of nodes with abstract obstacles.
* Mood: Not really any mood of which to speak.
* Genre: Strategy, I suppose, or puzzle-based.
* Gameplay: (As best I can recall.) You controlled a stick which swung between nodes (these could be different colors). The idea was to get from one part of a grid of these nodes to another, and the grid could contain obstacles (bad squares, electrical fields, things like that--I think.) Keyboard and/or mouse controls (computer game). Single-player. I seem to remember levels of increasing difficulty.
Mystery game the second:
* Background: On the internet, in a flash or javascript window. The way the little character one controlled moved sticks out to me: he jumped around in a more dynamically interesting way than one usually gets in flash games.
* Year: If I remember my summer camps correctly, it was in 2005.
* Perspective: 2-dimensional; one controlled a stick figure.
* Art style: Simple lines, some color. The evil eye (
http://en.wikipedia.org/wiki/Evil_eye) may have made an appearance, or maybe not. (I distantly, vaguely, and therefore unreliably associate it with this little game.)
* Environment: You had to get past obstacles to a goal. There were two-dimensional rocks you could jump onto and off of, or swing yourself around.
* Mood: I don't remember much about the mood; there may not have been much to remember.
* Genre: Single player; strategy/adventure/time-wasting flash thing on internet.
* Gameplay: There were levels, and I think the arrow keys and some other keys were used to move. The stick figure man could jump, like I've said, but his motion was fluid and he was able to grab onto things and swing, again, unsually fluidly for a game like this.
Pictures!

- A drawing which may help.
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Tangenitally related, is there a similar thread to this one for blogs of which one has forgotten the name?
Pure mathematics is, in its way, the poetry of logical ideas. —Albert Einstein