Which Mac, linux or Web GUI are you using for MongoDB.
A lot of projects seem to be very dead and I haven't succeeded installing a couple:
http://blog.timgourley.com/post/453680012/tuesday-night-tech-mongodb-ui-edition
http://www.mongodb.org/display/DOCS/Admin+UIs
Is anyone using a good one that actually works and is actively maintained?
Im using Mac.
MongoDB has a shipped with a REST Interface for the last few revisions. There's enough functionality there to get server and cluster details.
As for a UI, a standard console window is still the UI of choice. It's the best way to get familiar with the internals of the database. A UI is fine for casual use, but if you're going to use MongoDB in a production capacity it's best to understand its native administration.
Disagree with Acoustic here. It might be best to understand the native administration, but how often do you fall back to SQL*Plus or the SQL command line interface in MS SQL?
We use GUI tools because they are more productive. I think its a bit of a leap to imply that by using GUI tools we can't be familiar with the internals of the underlying tool.
I use MongoHub on my Mac to manage Mongo. For certain operations I do fall back to the command line, but not out of preference.
RockMongo - http://code.google.com/p/rock-php/
A full featured GUI tool for MongoDB, written in PHP5.
We release a new version every 10 days.