You get a monocle.

Inserts a toy mouse.

You get catnip
Inserts phone.

You get a piping hot pizza

Inserts table scraps

You get a clean plate

I'll insert a pacman

You get mass chaos.

Inserts a lava lamp.

You get: a live volcano

Inserts: a calculus textbook

You get gradient, divergence, and curl.

Inserts void

gets EXDEATH

inserts Yoshi plush

You get a large gold coin that slowly turns

I'll insert a pair of busted headphones

You get metal and plastic mainly, it seems the vending machine deconstructed the busted headphones

Inserts the bones belonging to a creature that was killed by being hit by a car

you get a reliquary with ashes.

inserts 3 1/2 floopy disk

You get a blue ray player
Inserts an apple keyboard.

You get the top of the line apple computer tower with monitor but there is no keyboard

I'll insert my 3GS iPhone and hope for better

You get a piece of pie.
Inserts some expensive cologne.

You get some Axe deodorant.

*Ilovehousepets inserts MY LOVE, MY ANGER, AND ALL OF MY SORROW!!!

You get a welcoming smile, a calming touch, and a loving caring hug.

I'll insert a box of home made chocolate cookies

You get melted box.

I insert the harbinger of death.

You get a randomgeeknamedbrent

I'll insert the code to a random safe

You get the code to another, different, random safe

Inserts a broken skeleton key

Hookshot get!

Insert fairy in a bottle

You get empty bottle

I insert occult artifacts.

you get Penn and Teller to harass you

insert a bullet with butterfly wings

You get a rat stuck in a cage.

Insert air conditioner

You get: a frozen metroid!

Inserts: a giant pizza


Side note: I can't believe I missed the chance to answer Ilovehousepets with a G Gundam reference!

you get a crumb *burp*

Inserts a random broom

You get a brand new mop

I'll insert some canned tuna fish

you get a toy stuffed tiger

inserts a Calvinball

You get: confusion

Insert: an ancient robot

You get an acient artifact

Inserts turkey sandwich

You get a note that reads 'Tastes like chicken'

Inserts some raw steak

You get a live cow.
Inserts a bean bag.

get a beanie baby

insert bacon

You get deliciousness.

Inserts blue police box.

you get busted
inserts 5,000 bucks fine

You get: a trip to the courthouse

Insert: a used toothbrush

You get a toilet brush

Inserts sour milk

you get: rotten cheese

inserts: used spark plug

get a figurine of Plugman from Megaman 9

insert lug nut

You get: a bluger-nut
Puts in: Psycotechnic energy

You get mental instability!!

I insert a computer virus...