Super Mario World (SNES)

Crazy Mario
After you defeat Bowser, and before the Princess floats down, press and hold Up until you see the credits. During the walk back to Yoshi's House, Mario will flap his arms and look up and down.
Exit level
In a level that you've already finished, press Start to pause and then press Select to go back to the Map Screen.
Re-enter Castles and Fortresses
On the map screen, stand on a defeated castle or fortress, then press L and R simultaneously to re-enter it.
Negative gravity
With Yoshi, you can slide uphill! While on a hill, just press diagonally down and either left or right, and he will slide up in that direction.
Musical Coins
In the row of five Music Blocks in Funky, the first two blocks keep giving you Coins for however long you can stay on top of them. Unfortunately, as soon as you touch the top of one of them, an invisible block forms on top of the Coin-giving Music Blocks, forcing you to the left and off the row of blocks. (The same invisible blocks prevent you from jumping on the blocks again for more Coins...) Try this: when you first jump onto the blocks, if you keep holding Right, Mario will stop at the end of the row of blocks and keep collecting Coins until you stop holding Right or time runs out, whichever comes first. Note: If you are Super Mario, you'll have to duck and jump onto the blocks.

Sent in by: RetroGameBoy

5 for 5
Sometimes you'll come across vertical chambers with five platforms, each with three ? Blocks on them (the first one in the game is found up the first pipe in Donut Plains 1). Two Coins and one 1-Up are placed randomly in the ? Blocks for each platform. If you don't hit the block containing the 1-Up last, the blocks will turn brown and you won't get the 1-Up. However, if you're Caped Mario, you can get the 1-Up every time. Starting from the left, spin-jump and whack the lower-left corner of each block with your cape. The last block in each platform will always yield a 1-Up!
Recycle P-Switches
Stomp a P-Switch, then quickly have Yoshi eat the bottom. Spit it out, and the switch will be restored! With this method, you can reuse the P-Switch as many times as you like.
Close encounter
If Mario stands one block-width away from a solid object and kicks a shell at it, the shell will ricochet off the object and pass through Mario without causing injury.
Cool lava
Vertical walls of lava are harmless. Experiment in Vanilla Dome 3.
Goalpost item bonus

If you carry something through the Goalposts, you'll get a power-up or 1-Up depending on what form Mario is, and what item you have in reserve.

Items in reserve
NothingMushroomFire FlowerFeather


Carrying a Key or a baby Yoshi through the Goalposts will always earn a 1-Up Mushroom.

Two for the price of one
If you put two items down on almost the exact same space, you can pick both items up at once by holding X or Y as you walk into them. You can throw both items up at a block that contains a item, and you'll get two of them! Or pass through the Goalposts, and you'll get rewarded for both items.
Put an item down where Yoshi is standing. Hold X or Y as you jump onto Yoshi. If the item was in the right spot, you'll now be carrying the item while riding Yoshi!
Quick points
Either be Fiery Mario with a Cape Feather in reserve, or Caped Mario with a Fire Flower in reserve. Find a high platform, get direcly under your item reserve box, and keep pressing Select. You'll get 1000 points every time you get the Cape Feather.
Multiple 1-Ups

For each enemy you stomp without touching the ground, you'll earn more and more points, and eventually 1-Ups. The score for each enemy stomped will be: 100, 200, 400, 800, 1000, 2000, 4000, 8000, then 1-Ups for each enemy thereafter. Remember: Fences and vines don't count as ground!

Similarly, when you kill enemies with a Shell, from invincibility, or when you go through Goalposts, the score for each enemy increases the same way. But when you activate a Gray P-Switch, Gray Coins collected will increase up to 8000 points, then a 1-Up, a 2-Up, and 3-Ups for the rest.

Mega 1-Ups: Vanilla Secret 2
Get the Gray P-Switch from the second block by the row of Spinys, and take it back to the Midway Gate. Stomp it, then run to the left. All those Winged Koopa Troopas from the beginning become Gray Coins! Getting over 50 extra lives in this level is not uncommon.
Mario's fireballs can take out three Koopa Kids: Morton, Ludwig, and Roy. This kills them nice and fast...
Stay on the Special World map screen for a while, and eventually a steel-drum version of the famous Super Mario Bros. theme will play.
The magic number
For an extra 1-Up at the Goalposts, match the the tens and ones digits of the time remaining to the tens digit of the number of stars you got from breaking the tape. Example #1: 233 left on timer, and 30 stars from the Goalposts. Example #2: 200 left on timer, and 4 stars (equivalent to 04 stars) from the Goalposts.
Eight it up

When you get 100 total stars from breaking the tape at the Goalposts, you'll enter a bonus game where you can win up to eight 1-Ups. If you have good timing with your jumps, here's how you can get eight 1-Ups easily. First, keep pressing Start to pause the game until you see the item in the middle come up in the bottom row. Look at the floor directly underneath the block in the bottom row, then unpause and walk to that spot. Now all you have to do is jump straight up to hit the blocks when they're directly above you, and you'll match the item in the middle every time.

Coin formations

Some groups of Coins take the shape of arrows; follow them!

The Coins at the end of Funky spell: YOU ARE A SUPER PLAYER!!