Note the "WIP." This currently has 12 tools in the Tool Gun plus a Phys Gun if you don't want to download my gravity guns. Feel free to suggest any new tool ideas.

Current Tools:
1. Cloner - Clones stuff.
2. Cloner Pinned - Clones stuff and pins them on creation.
3. Remover - Removes stuff.
-New- 4. Welder - Attaches 2 objects together.
-New- 5. Weld Remover - Removes all welds on an object.
-New- 6. Balloon Tool - Attaches balloons to objects.
-New- 7. Thruster Tool = Attaches thrusters to objects.
8. Emitter Controller - Toggles an emitter's emission.
9. Device Controller - Operates HDFirearms and TDExplosives.
10. Actor Controller - Switches your control to the selected actor.
-New- 11. Health Controller - Adds or subtracts an actor's health.
-New- 12. Object Spawner - Opens up the build menu.

Controls:
Press Fire to start the Tool Gun and bring up a cursor.
Up/Down/Left/Right or Mouse - move cursor.
Fire - Primary tool function.
Crouch - Secondary tool function.
Jump - Bring up mini-menu.
Jump + Left/Right - Swtich tools.

Tool Controls are listed in while using the tool.

Change Log:
(1-24-10)
- Added Welder
- Added Weld Remover
- Added Balloon Tool
- Added Thruster Tool
- Added Health Controller
- Added Object Spawner

Is there anything you can't do cavecricket? Downloading now... will edit later after use
Edit: A couple of thoughts:
Can you make weapons controlled in device mode of the tool gun shoot with sharp aim accuracy?
The cross hair for the tool gun (or at least the device controller) has an mopixel trail that damages any actors or devices it comes into contact with
Also I can't wait for welder functionality so I can attach bombs to the other teams units and then control them right into the brain room.

Exactly. As discussed before, it is time to feed him to Data to speed up CC development. Our master will make good use of use a brilliant brain.

GJ cavecricket. Once again.

Probably my favorite thing from you since the Cloning Factory, great work. Oh, and I have a suggestion for you: Maybe you could make the cloner tool copy at least the first three items in the actors inventory? If its hard to implement since it also clones weapons and whatnot maybe you could make a separate tool, another thing is since it's practically the duplicator tool, maybe you could just rename it that?

Have you been replaced by a robot or something? Because no human can keep up this pace of awesome modding for so long.

You are a machine...
Requesting balloon tool and inflater tool.

No, he's a badass super cyborg.

Really surprising mod I must say, manipulating stuff is fun.
I could suggest these additions:

Basic terrain creation/erasing powers.
Simple interactive objects that can be created by the tool such as:
-24x24px and a 48x48px MOSRotating block
-A simple fire emitter (rocket thruster)
-And perhaps more, but thats what I can think of right now.
Team changing and AI mode setting abilities. (Turn a guy into an enemy and give him a goto point or make him dig for gold.)
And finally a tough/invincible actor that can fly around freely like a god.

If I remember right, the code for actor team switching was quite crashy.

Ofcourse, you could just delete it and make a new one on the other team at the same location with the same inventory.

Wow CaveCricket are you a super modding computer/cyborg/crab? well as always this is a great mod, i wonder if your have an unlimited supply of awesomeness Energy drink because all your work is simply amazing

I CAN'T BELIEVE YOU MADE THE TOOLS FROM GARY'S MOD. The reason I'm so surprised is because knowing you, I know you're just gonna keep making this mod more and more awesome. I think you should be able to bring up the buy menu from the beginning of skirmish with it.

The buy menu already comes up in the start of skirmish.
If you're talking about the bunker buy menu, someone made a mod that does that already.

I know someone already made that but it doesn't work for me. Besides, that's pretty much what the tool gun can do in Gmod.

what does the emitter controller do?

It says in the OP and the tool text: "Press FIRE over an emitter to enable it and CROUCH to disable it." Meaning it turns emitters off and on.

Edit: Oh and update:
6 more tools:
Welder
Weld Remover
Balloon Tool
Thruster Tool
Health Controller
Object Spawner

Turns emitters on and off. Read the OP, please.
NINJA'D.