I love obscure tribal decks and decks with a really odd and not often played theme. So far I’ve made the following decks in order of favorite to least favorite:

1. Unicorns (the most amazing tribe in the history of ever): Unicorns! (My EDH Masterpiece)
2. BW Lifegain/Control: Karlov the Ghost Daddy's Weight Loss Program
3. Eldrazi: Eldrazi Speedracer
4. Pure Chaos: CHAOS! CONFUSION! POWER!
5. Boros Equipment: Ardenn Equipment Mania
6. Respect your "Elders": The Senile Old Farts
7. Mono-Red Everyone Draws Cards: Devilish Draws N Damage
8. Put counters on (and goad) your opponent's creatures: Cookies...er..Counters for Everyone!
9. Treasure.dec: Tiamat’s Treasure Hoard
10. A deck based around the word "Unless": "Unless" (A Deck for Sadists)
11. Tons of value from playing multicolor cards: Multicolored Goodness
12. The "Nic" deck: The "Nic" Deck
13. Enchant (and goad) all of your opponent's creatures: Kaima, the Charitable
14. Give bad gifts to opponents: Creepy Donations
15. X Spells with Hinata: Hinata Hates Everyone Equally
16. Cards with flash and etb effects: Splashy McFlashy
17. Avatar Tribal: Avatars, but not the Airbending Kind
18. Dwarves and Vehicles: Budget Dwarves/Vehicles
19. Enchant opponent's creatures in BW: Oops! All Pacifisms
20. Morphs (with Kaust): Bigger than they Look
21. Mono Black Enchantress: Horobi Enchantress
22. Morphs (with Animar) (retired): Morphs "Will bender" your mind O_o
23. Mono-White Equipment (retired): Balan Equipment Mania
24. Saprolings/Ghave good stuff (retired): Saprolings Unhinged
25. Prismatic Bridge and Fatties (retired): deck:BIg dUMb CrEAtUrES!
26. Golgari Destroy all the things (retired): Chevil: None Shall Escape the Slaughter
27. Coin Flip (retired): Freaky Flip Tribal
28. Simic Auras (retired): Ivy and her Mystical Auras
29. Unicorns V.2 (It's all Unicorns and you can't convince me otherwise) (retired): Unicorns v2.0.... or is it???
30. Pegasi (the second most amazing tribe in the history of ever even though it is ranked lower than eldrazi and elders) (retired): The Second Best Tribal
31. Landfall and Sea Creatures: (retired) The Landsharks
32. Enchantress pillowfort (retired): Fluffy Enchantments
33. Haste Tribal (retiured): The Speedy Bois
34. Mono Blue Scrying (retired): Go Scry About it
35. Shadowborn Apostles (retired): Shadowborn Apostle Death Sentence
36. Proliferate good stuff (retired): Atraxa Energy/Proliferate
37. Board Wipe in the Command Zone (retired): Piru, the Thirsty
38. Deathouch becomes infect (retired): This Deck is Toxic
39. Pile tons of counters on the commander (retired): The Odd Counter Cat
40. Wizard/Warrior/Cleric/Rogue party good-stuff (retired): Tazri's Party Pals
41. Wurms (retired): WUUUURMS!!!
42. A deck where every card is random (retired): Random Tribal
43. Lands, and basically nothing else (retired): Lands... and basically nothing else

I also have two deck lists on this site that I helped my wife make. The first deck centers around Mowu, Loyal Companion, and the second deck focuses on as much flier synergy as possible with Alela, Artful Provocateur as the commander. I'm not going to rank those decks since they aren't mine, but the fliers deck is definitely more fun than the Mowu deck.

I have several decks that I am in the process of brewing, and I will list them when they are finished.