you can't really make 'unportalable' surfaces. 

It's a map I made for Doodle project (http://www.doodlethegame.com/), screenshots were taken with DP:

Full gallery:
http://shadowsdomain.wordpress.com/gallery/doodle-map/

http://shadowsdomain.files.wordpress.com/2011/08/de1m1_01.jpg
http://shadowsdomain.files.wordpress.com/2011/08/de1m1_04.jpg
http://shadowsdomain.files.wordpress.com/2011/08/de1m1_09.jpg 

That looks great. 

looks like a preview render in 3dsmax. ^_^
nice brushwork! 

That's beautiful, ShadoW. Is that a high-res texture? I would not have thought you could get pure smooth white with quake's original textures. 

i thought it was fitzquake with r_lightmap 1. 

The doodle project appears to have its own engine based on NPRQuake, but he mentions in his OP that the "screenshots were taken with DP" which I assume means darkplaces. Does Darkplaces have r_lightmap 1? 

just checked. if it does, it's not r_lightmap. possibly just used all greyish textures?

should have realized it wasn't r_lightmap, actually, because the ammo box and monster in the shot are still textured. 

I wish all leaks were this simple 

using hmap2? 

from the top. 

Was a path node very obviously in void space :p 

Screenshots were taken with Darkplaces. No idea about r_lightmap during making them :P. Map was compiled with BJ tools. Texture is just plane white :). 

Bit of progress on a room you're in for about five seconds

Started a smaller Base level out of boredom 

... really nice ! 

ZealousQuakeFan why don't you split the level in two? 

I hate this base/standard style..
..too orthodox, boring, old if you can get what I mean :)

you could try change theme for example 

Same here. Original base wasn't never that great to start with - the weaker of the Quake styles. There's plenty of newer base textures to use without sticking with the originals that we've already had 500 others maps in. Just my opinion though. 

atm Base is the only theme I have any confidence with :p 

Try combining idbase with something else.

Try having a theme.

Use new textures / models. 

http://www.quaketastic.com/upload/files/screen_shots/rock.jpg 

awesome Mechtech 

Maybe a bit too much color. Took me days to add the green waterfall, just before preach released his waterfall tut. Creepy colorchannel.

http://members.home.nl/gimli/torm00.jpg
http://members.home.nl/gimli/torm01.jpg
http://members.home.nl/gimli/torm04.jpg 

Looks good, I especially like the last screenshot.

Try switching on antialiasing for screenshots though.

Criticism: The texture alignment on the pipes needs work; try to make the plates fit the width of the pipe's side. Just scale and rotate the textures as needed. Alternatively try using simpler textures on the pipes.

The colour of the lava doesn't fit completely with the rest - have you considered slime instead of lava?

A tiny amount of fog might look pretty good here as well.

I really like the overall look of it though. 

look's great madfox :) and all look alight!

:)