Dies to Removal

Canadian hoser, eh

Deck: Ad Nauseam Lightning Storm

Win-Con: Protect for a turn with either Angel's Grace or Phyrexian Unlife, then cast Ad Nauseam to draw every card in your deck. Cast Lightning Storm with Simian Spirit Guide and discard lands to make a lethal Lightning Storm.
Plan B: Combo using Conflagrate instead.

Problem Cards: Pact of Negation, artifact mana, Angel's Grace / P. Unlife.

Hosers

White: Rule of Law, Leyline of Sanctity, Angel's Grace
Black:
Red:
Multi-color: Hide // Seek (exile the win-con, they'll scoop)
Hybrid:
Artifact: Spellskite

Will write more later

Deck: [mana]UR[/mana] Storm

Win-Con: Using red rituals (Desperate Ritual) and blue card draw/cantrips (Serum Visions, Manamorphose, Desperate Ravings), chain together spells until a Grapeshot can be cast to win in 1 turn. An active Pyromancer Ascension and can be attained to make this easier.
Plan B: Empty the Warrens and win through attack damage.

Problem Cards: Goblin Electromancer, Pyromancer Ascension, Past in Flames

Hosers

White: Rule of Law, Rest in Peace, Thalia, Guardian of Thraben, Spirit of the Labyrinth, Leyline of Sanctity
Black: Leyline of the Void
Red:
Multi-color: Rakdos Charm
Hybrid:
Artifact: Trinisphere, Grafdigger's Cage, Relic of Progenitus

Deck: [mana]RG[/mana] Tron

Win-Con: Using artifacts and green search spells, search the library for 1 each of Urza's Tower, Urza's Mine and Urza's Power Plant for a turn 3 Wurmcoil Engine or Karn Liberated.
Plan B: Stall with board wipes and hardcast Wurmcoil Engine or Karn Liberated.

Hosers

White: Path to Exile, Stony Silence
Black:
Red: Blood Moon, Sowing Salt, Shattering Spree, Shattering Blow
Multi-color: Rakdos Charm, Hide // Seek
Hybrid:
Artifact: Ensnaring Bridge

Deck: Melira Pod ([mana]WBG[/mana])

Win-Con: With an active Viscera Seer and a Melira, Sylvok Outcast, sacrifice a creature with Persist (Kitchen Finks or Murderous Redcap) to do an unlimited damage or gain an arbitrarily large amount of life.
Plan B: Use Birthing Pod to search the deck for singleton creatures that hinder your game plan, attacking every turn and making their creatures better with Gavony Township.

Hosers

White: Path to Exile, Rest in Peace
Black: Leyline of the Void
Red: Blood Moon
Multi-color: Rakdos Charm
Hybrid:
Artifact: Relic of Progenitus, Torpor Orb, Grafdigger's Cage

I play Modern primarily with my Dega ([mana]WRB[/mana]) brew so I'll include a list of relevant sideboard cards in these 3 colors vs prominent decks.

Deck: URW Splinter Twin
Win-Con: Infinite attacking creatures on turn 4 with Splinter Twin on a Deceiver Exarch, Pestermite or Village Bell-Ringer or turn 5 using Kiki-Jiki, Mirror Breaker and Restoration Angel.
Plan B: Combat Damage and burn
Problem Cards: Splinter Twin, 4 toughness creatures.

Hosers

White: Suppression Field, Disenchant
Black: Illness in the Ranks, Dismember
Red: Combust
Multi-color: Rakdos Charm, Hide // Seek, Zealous Persecution
Hybrid: Batwing Brume
Artifact: Spellskite, Torpor Orb