Five most useful MineCraft mods

These are the first five of what I consider to be the most useful Minecraft mods. I'll probably do several of these.

1. Magnet Mode:
This mod causes all dropped items to be "attracted" to you. Sometimes, it can be a nuisance, but if you want to get rid of stuff, dig a hole two blocks down, drop what you do not want, and stay away from the hole until the item despawns.
Usefulness Factor: 10. It's invaluable when mining or fighting creatures, as you can collect drops without running over them.
Watch it work: Video here (It's not in english, but you can see the mod in action. Start watching at 0:42 to see an example.)

2. TreeCapitator Mod:
This mod makes the entire tree fall down when you chop down one block, excluding wood below the chopped block. You need to use an ax for it to work. It also removes leaves and leaves the saplings or apples to be picked up. (THAT was a weird sentence.) It only uses ONE block removal on the ax.
Be warned--there are at least three versions of mods like this. They are DIFFERENT:
1. TreeCapitator mod (my preferred one)
2. One that only removes the wood, and leaves the leaves (AGAIN!) to rot. (GabaTron's Farming Pack has this version.) (Timber mod.)
3. One that uses up as much of your ax as chopping down every individual block would. This one is obnoxious, and can be found in Yogbox 1.6.4. It often leaves half the tree left if you chop down a huge tree, and all that's left is (conveniently) out of reach.
Usefulness Factor: 10. Invaluable if you hate chopping down trees.
Watch it work: Video here Just watch the whole thing. It's in English this time.

3. Inventory Tweaks:
Did your pickax (or other tool) just break? Don't worry. If you have another in your inventory, it's now in your hand! You can also sort your inventory and chests with one click, and it stacks things like empty buckets in your inventory automatically.
Usefulness Factor: 10, just for the tool replacement.
Minecraft Forum Topic: Click here

4. Dynamic Lights Mod:
You're walking into a cave holding a torch and it's dark. Wait, what? Not anymore--this mod fixes that. Jack-o-lanterns and glowstone have the same effect.
Usefulness Factor: 8.
Watch it work: Video here

5. OptiFine:
DOUBLE your FPS. Many players get 100% more or higher FPS with OptiFine.
Usefulness Factor: 10. My laptop would not play many mods nicely enough, and OptiFine fixed this. I use it on the desktop, too.
Minecraft Forum Topic: Click here