Here are some helpful things I found on other halo modding forums regarding scripting and other hot topics. Although the information is primarily geared towards Halo Custom Edition editing, I recommend you read them for general knowledge.
CE tools list
A quick note about falling damage and physics
Camera focus depth and cinematics
EHS (Easy Halo Scripter) v2.0 forum topic
and Gearbox Software Forum topic
EHS v2.0 filefront download
Backpack weapons mod forum topic
(CE modding, but worth reading)
Discussions regarding devices (machines) and their scripting; also mentions multiplayer device sync-ing issues, similar to the AI issues we know about now.
Manually editing Gametypes
Picking up vehicles with the pelican
Multiple BSPs, making new single-player maps and cutscenes
Converting UT maps, translocator gun, etc.
A CE multiplayer map with AI.
Discussion about sync-ing AI and other relevant chit-chat
A flash file (with link to a cool CE mod) that is found in Stuntman's signature
Very long list of scripting variables (more comprehensive than the standard, mostly for Sapien)
You'll notice that they aren't necessarily usable in Halo; read the all the replies.
An in-depth look at scripting
Some advice on scripting
(don't bother reading the whole thing)
How to PWN a banshee noob
General Halo Editing Tutorial Links (Ghost)
Note that not all the links work. Don't bother clicking the Wiki ones, they're dead.
How to make your own HMT plugins (works with Eschaton, of course)
Setting up Notepad++ to work with Halo Scripting
as an alternative to the EHS linked above, I guess.
Script used for deleting objects
How to make it snow
Online Halo Scripting Bible reference
Please use the scripting topics linked above in conjunction with this reference, for greater understanding.
Collision vs. Physics Models
MGM Halo References and Tutorials:
Xenoku - Combat Rifle (Spew time tutorial)
002 - Placing Deadly Traps
(Multiple) - Tag Duplication Tutorial
Moxus - Renaming Tags
Tyler777 - All Halo's Variables
Tyler777 - Extracting sounds from Sounds.map
Blackhat - Queen Anne's Revenge
Multiple - Note about rebuilding maps with HHK
Sparky - Glowing Spartan and other flashlight-related effects
>Shadow< and Beast - Cheat files
(3rd-person, cloner, extended radar, flying hogs, no fall damage, speed hack, name changer, score hack, starting weapons changer, teleporter changer)
Tyler777 - Tyler's Cheat Thread
Tyler777 - Third-person view
Tyler777 - Cheat Servers
(how to let other cheat on your server)
A Woman - Notes for MGM's visitors and those new to modding
Sword - SwordEdit: Genesis
SilentK - A look into Halo's Structures
(just ignore his first post)
Kiyoshi - Exploding Vehicles
BlackHawk - Personal Hog
(repositioning players in the warthog)
Sparky - Halo 1 Tag List
Fonzie - Additional HMT Plugins for Eschaton
Multiple - Vehicles taking damage
A Sniper - Duel-Wielding Pistols in Halo Demo
Multiple - Removing the HUD
to be continued...
Comments? Questions? Addendums? Flashing lights and dancing girls?
EDIT: Thanks for the sticky, Monoman - that was completely unexpected
I'll clean up the organization at a later date, sorting by subject. I guess it would also be o.k. to add links to our tutorials, so those will go under the "MGM Halo References and Tutorials" section that will also be categorically sorted.
Either you are groping for answers, or you are asking God and listening to Jesus.