1)Have a solo dance party.
2)Teach yourself how to do an Australian accent (or any accent for that matter).
3)Learn how to play harmonica (or any instrument for that matter).
4)Buy an at home workout DVD.
5)Bake a cake (and eat the whole thing for yourself).
6)Take a rollaway chair and ride it down the driveway.
7)Paint a self-portrait.
8)Plant some flowers in your backyard.
9)Become a master at air-guitar.
10)Perform a concert (just for yourself).
11)Write a novel.
12)Become an expert on quantum mechanics.
13)Give yourself a new hairdo.
14)Knit a sweater (if you don't know how, learn).
15)Make a bunch of origami paper cranes and decorate your house with them.
16)Make homemade popsicles.
17)Reorganize your entire closet.
18)Put together a funky new outfit.
19)Make a short film.
20)Try to hold a handstand for as long as possible.
21)Memorize the lyrics to all of your favorite songs.
22)Create a website.
23)Go on Club Penguin and troll a bunch of children.
24)Become your favorite fictional character.
25)Become your favorite animal.
26)Practice your autograph for when you become famous.
27)Create a magical potion.
28)Learn a few spells.
29)Learn how to become a Jedi.
30)Put the TV on mute and overdub it with your own voice.
31)Make paper hats with old newspapers.
32)Become a master at jump roping tricks.
33)Create music playlists based on random things, like colors.
34)Find a chunk of wood and carve something out of it.
35)Find something that doesn't have a Wikipedia page and create one for it.
36)Create a full course meal based on whatever's in your kitchen.
37)Teach your pet a new trick.
38)Take a bunch of artsy photographs.
39)Make a scrapbook.
40)Learn a bunch of new words and incorporate them into your speech.
41)Try to draw the most perfect circle without using a compass.
42)Make your own board game.
Memorize some poetry well enough so you can recite it.
43)Build a fleet of sailboats and float them in your bathtub/pool.
44)Write a song.
45)Practice picking locks.
46+47)Make a drum kit out of random household items and play it.
48)Draw a tattoo on yourself.
49)Give yourself a new piercing.
50)Figure out the meaning of life.