Random Spawn Egg (Creative only)
When use it spawns a random mob. Can be configured to blacklist or whitelist (If whitelist:true) certain mobs such as enderdragon by default should be blacklisted.

3 way Redstone Randomizer
Pretty much says it... It takes one input at one side, and the 3 others will randomly go on and off.

Random Meat
Crafted by putting all raw meat together, including rotten flesh and spider eye, with a red mushroom. Will always give Nausia, but with added random potion effect... To increase the chance of positive potion effect it's to craft the random meat with ghast tears, or negative potion effect with gunpowder. Random Meat won't stack. This can be used to troll a friend too.

Random portal
Main portal block is crafted with dirt, cobble, sand, water bucket, obsidian, lava bucket, end stone, netherrack, and purpur block. The portal frame is basically 4 Random portal blocks at the corners and dirt... yea dirt... in the same configuration as a nether portal. This portal can randomly teleport players anywhere in the world... randomly. With a random chance to end up in the Nether or End... Risk of falling into lava or void. Beware.

Random Things
Crafted using all the random items above (2 to 4), with a redstone tool, and the rest Ectoplasm. It will create a wand that can make items go crazy. Use it on wool placed blocks, carpets, and beds and they will change color like the jeb_ sheeps, use it on torch, redstone torch, and redstone light, and they will flicker, use it on a zombie... The return of the Giant Zombie!!! or baby zombie. This can bring more ideas.