Super Smash Bros. Melee/Kirby

Throws
Kirby's Grab is very short range, but it's lightning quick, making it easy to use while dashing past an opponent.

Suicide Swallow
Swallow someone then jump off the ledge (which would leave a long time for the swallowed opponent to escape). A much better way to do this is when an opponent is right on a ledge, jump off the edge and on your way down, inhale them. This works very well on larger stages with more room on the sides, such as Hyrule Temple.

Super-Invincibility
Jump and use Kirby's Stone (Down + B). When Kirby falls, he will be invincible for a short period, at which point no enemy can touch him, and he can easily detonate Motion-Sensor Bombs/Bob-bombs or trigger Flippers/Wobbuffets without being hurt. He is vulnerable to grabs, though.

Suicide Throw
If used near the edge, Kirby's back throw brings both fighters down. The fighter who is grabbed will hit the bottom first. Keep in mind, if the grabee breaks free during the front flip, Kirby will dive to his death alone.

Kirby Bomber
Using Kirby's multiple jumps fly up above your opponent as far as you can and then use down+B to come crashing down into your opponent and then repeat for as long as your foe is foolish enough to remain out of cover, but beware of Pikachu's Thunder, as it can easily ruin this tactic.

Peaceful Warrior
In some stages (Icicle Mountain and Poke Floats are best), you can just fly around and keep from falling while your opponent scrambles about. Not for long battles.

Edge Spitter
Some stages (like Flat Zone and Super Mario Bros.) don't have cliffs on the edges of the screen (the left and right sides). You still lose a life if you walk off them. But how to get your foe to walk off them? Don't. Spit them off by sucking them up, turning around and pressing A. This trick is awesome.