Utility Macros for Mages 2.x
Credit to Zarakaar, Dalaran-US.

Mana Gems
This macro sequentially conjures all your mana gems on right clicks, and uses the highest level one available on left click. As a fall-through macro, this will cause error messages when used to consume gems.

/castsequence [button:2] reset=120 Conjure Mana Emerald, Conjure Mana Ruby, Conjure Mana Citrine, Conjure Mana Jade, Conjure Mana Agate
/stopmacro [button:2]
/use Mana Emerald
/use Mana Ruby
/use Mana Citrine
/use Mana Jade
/use Mana Agate

Evocation
First two clicks equip your spirit weapons, third click casts Evocation. Right clicking puts back on DPS weaponry.

/castsequence [button:1] reset=10 Serpentcrest Life-Staff, Marli's Touch, Evocation
/stopmacro [button:1]
/equip Time-Shifted Dagger
/equip The Saga of Terokk
/equip Nether-Core's Control Rod

Food & Water
This macro has you eat and drink with a click, conjure water with shift-click, and conjure food with shift-right-click.

/use [nomodifier] Conjured Glacial Water
/use [nomodifier] Conjured Croissant
/cast [modifier:shift, button:2] Conjure Food;[modifier:shift] Conjure Water

Smart Dampen/Amplify
Left clicks Dampen Magic, right clicks Amplify; if your target is in your party, it buffs him, otherwise it buffs you instead.

/cast [button:2, party] Amplify Magic; [button:2, target=player]Amplify Magic; [party] Dampen Magic; [target=player] Dampen Magic

Self Buff Sequence
Insert your own favorite soloing buffs, and press one button three times to cast them.

/castsequence [target=player] reset=600 Dampen Magic, Arcane Intellect, Mage Armor

One-Button Wards
Left click for Fire Ward, right click for Frost Ward

/cast [button:2] Frost Ward; Fire Ward

One-Button Armor
Click for Mage Armor, right click for Molten Armor, alt-click for Ice Armor.

/cast [modifier:alt]Ice Armor; [button:2]Molten Armor; Mage Armor

One-Button Portal
Useful for those below level 65 to get around and help their friends get around. Click to portal to Ironforge (Orgrimmar), alt for Stormwind (Undercity), control for Darnassus (Thunder Bluff), and shift for Exodar (Silvermoon).

/cast [modifier:shift] Portal: Exodar; [modifier:alt] Portal: Stormwind; [modifier:ctrl] Portal: Darnassus; Portal: Ironforge

/cast [modifier:shift] Portal: Silvermoon; [modifier:alt] Portal: Undercity; [modifier:ctrl] Portal: Thunder Bluff; Portal: Orgrimmar

One-Button Teleport
Here’s the same thing as the Portal macro, but just for you. It’s not useful past level 59.

/cast [modifier:shift] Teleport: Exodar; [modifier:alt] Teleport: Stormwind; [modifier:ctrl] Teleport: Darnassus; Teleport: Ironforge

/cast [modifier:shift] Teleport: Silvermoon; [modifier:alt] Teleport: Undercity; [modifier:ctrl] Teleport: Thunder Bluff; Teleport: Orgrimmar

High Level Portal & Teleport
Once you’re level 65, this will get you anywhere. Click for portal, right click for teleport. This one’s even the same for Horde and Alliance.

/cast [button:2] Teleport:Shattrath; Portal:Shattrath