Mine has to be 'Metropolis' It took me an average 2 years to finish and polish the extra's on the map. It has 15,000 + Hits/Downloads and won 2nd place in a Mapping Competition in 2008 Or 2007.
Edited 4.05 minutes after the original posting.

I'm currently producing my first map ever made for Quake 3 Arena, so that's the best map that I'm making at this point in time.

mmm prolly q3dmp15. but due to texture issues it never saw the light of day :(

@fKd: Some of those texture could have been replaced with some of evillairs other (non commercial) textures. Do you know what map you got the textures from? Was it PhobosBase1?

Hmm, I think my last and also best map was The Longest Capture - czg3team1 (TA remake from Q3dm17), CZG3 maps are gone, now the CZE3 maps will get to scene...

@CZghost: I loved the map 'The Longest Capture' It was so amazing and a brilliant experience.

@fKd: Your map did have a few texture issues but i got to say it was pretty fun.

@Everyone: I will try to psot my best map 'Metropolis' On this website as soon as possible. Sadly i cant find the file on the computer but ill try my best.

I'm in a drought of inspiration and I have no Quake 3 map released but I can say that it's a tie between tsh2tourney1 (Quake 2) and DM-InsularGW (Unreal Tournament).

Intresting.. I design maps for UT2004 and UT3. My best map i designed & created for UT2004 was 'Terrorism World' It had over 25,000 hits/downloads.. You can check it out on mapraider.com.. If its still there.

Lol i'm creating a very junky map of space but it's gonna be the worst map ever... Because i'm only thirteen years old and I'm Dutch so I am not good at English, and i got no experience XD
So, i don't know how to publish the map... (Can anyone help me???!! (I'm using GTKRadiant))

Alexje, there's a German tutorial by DaEngineer, but I don't think there are any Dutch tutorials out there. Your English seems quite good though - better than many English-speaking people! You could visit the sticky threads in the Level Editing board in Quake 3 World's forums with Google translate: translate.google.com/translate

@Alexje60: themuffinator is right :). Use the tutorial by DaEngineer that will help lots.

Quantity over quality hey Frag...

@themufinator: Yup you got that right Muffin :).

I've never finished a map, I have so many ideas in my head and I start doing the idea and before I know it there's another idea in my head. If you looked at the amount of unfinished shit I have you'll think there's something wrong with me.

@Satan Fang: Just think of an idea you think that will make your map popular. I'm currently working on a Saw themed map. It's going to have rooms with traps and also you can hear Jigsaw's voice. It's kinda creepy since I tested it out but it's unfinished. I'll post the map when it's done. It may take a couple of weeks or months.

The map I've worked most on is The Gloom, but I doubt it'll be very good. Most people have come to me and say it's focused more on experimentation rather than gameplay and most Quake fans prefer gamplay anytime.

@Satan Fang: Gameplay is important in custom maps. If the Gameplay is laggy then there is no use but if the Gameplay is good, then you might as well just let us have a go at the map. If you dont think your confident enough to post the map, Test the map out with 2 - 4 or more to see if Gameplay is good.

It is posted, just fallen to the bottom.

@Satan Fang: That's great if you posted it :). I'm gonna test it and write a review on it.

It's not even finished, I meant I posted it in the forums.