Map name:
Gutter
Quick detail:
The player must gather his weapons and fix an old combine teleporter in a nearby refinery to resume his journey.
Long detail:
The malfunctioning teleporter transports the player to an old, abandond and derelict refinery near the coast. The refinery houses an old teleporter experiment by the combine, but is currently not fully operational and need power to work again. During the transmission, the player looses all his/her weapons during the entry to the refinery which are needed to navigate the refinery and locate the power switches needed for the teleporter.
Gameplay:
No combat so far (not against AI at least). There will be focus on navigation and returning to previous areas with new weapons in order to reach other parts of the refinery. Example on puzzles will be navigating small ledges, jumps, gravitygun push & pulls, shooting padlocks and barrels, airhandling down sharp declines and using the suit sprint to reach time limits.
Realistically I don't see every idea being implemented, but of all the ideas I've jotted down the above ones are what I'm currently going for.
Current progress:
27.06.14:
Finally got gotten the map to a somewhat presentable state and have barely managed to suppress my desire to immediately start detailing a room after I have given it four walls, a ceiling and a floor and rather do some general brushwork to get the gameplay elements in first.
So far I've managed to orange-map the starting area (gutter), the teleporterhouse ( with a short sequence where it looses power) and a quest to retrieve the HEV suit and gravity gun so you can access the first power switch. During the this map there will be perilous jumps, time constraints, sliding down sandpits, gravity gun and guardhouse vandalism.
Some screens of the current map:
The teleporter house and the first power shack. As it currently stands, the teleporter house is the first and last area the player will visit.

The observation hut and guardhouse with the silo in the background. The black devwall will hopefully become a mountain one day.

The silo tower. There's currently just a ladder up, but I hope to make some rickety scaffolding to make the ascent slightly more perilous.

A side-view of the entire map with some rough explanations to flesh out the areas.

Feedback and Download:
If anyone is interested in trying it and giving feedback on how it feels to play and how the mechanics are working for you then I would be very grateful.
Link to the .bsp:
https://www.dropbox.com/s/30oc8lilrje9z77/gutter.bsp
-Sloprano