Some nifty tricks I've learned using a classic Trap: Magical Hats

Trick 1: Tribute Summon on their Turn
The Spell/Traps used by Hats are treated as Monster cards. If you use it with Ultimate Offering, you can get out a big hitter like Blue-Eyes, or one of the Hierartics, or even a God card.

Trick 2: Pick a Card, any Card

This combo is a little more situational, but it works. You need Hats and a Penguin Soldier. Using Hats, fetch ANY 2 Spells or Traps you need. Then you can either let the Opponent get lucky on hitting Penguin, OR use Acid Trap Hole to auto flip him, causing his effect to trigger. Target the two "Hats" you just got and tada! Instant Spell searched!