I sometimes use macros that change based on whether a target is friend or foe while using the same keybinding. Typically I use healing spells that are spammable that alternate with damage or CC spells that are also spammable.

For example, a shaman who wanted to cast Healing Wave on a target that is friendly or Lightning Bolt on a hostile target.

#showtooltip [help] Healing Wave; [harm] Lightning Bolt; Healing Wave

/cast Lifeblood

/cast [help] Healing Wave; [harm] Lightning Bolt

Notice the tooltip updates depending on your target hostility with the healing spell shown when the target is neither friendly or hostile or when you have no target. My shaman also happens to be a herbalist so I have lifeblood in there too. You can add trinkets to auto pop if you want.

Other examples of this macro type are as follows:

Purge a harmfull target of buffs or clense a friendly

#showtooltip [help]  Cleanse Spirit; Purge

/cast [harm] Purge; [help] Cleanse Spirit

I have a warrior and I use one button to charge a hostile target, intervene a friendly, or heroic leap with no target.

#showtooltip [help] Intervene; [harm] Charge; [@none] Heroic Leap

/cast [harm,exists,nomod] Charge; [help,exists] Intervene; [@none] Heroic Leap

Another macro I use to save some a button space is a interrupt macro. It skull bashes in cat or bear depending on what form I am in.

#showtooltip [stance:1] Skull Bash(Bear Form); [stance:3] Skull Bash(Cat Form)

/cast [stance:1] Skull Bash(Bear Form); [stance:3] Skull Bash(Cat Form)

I know there are mods for mounting but I have a macro that makes me fly if I can, ground mount if I can, cheetah if in combat, seal if I'm swimming with one button.

/cast [swimming] Aquatic Form(Shapeshift);  [flyable,nocombat] Swift Flight Form(Shapeshift);[nocombat] Golden King; Travel Form(Shapeshift)

If not a druid can change the macro to at least choose between a ground mount or flying mount like this.

#showtooltip [flyable] Violet Proto-Drake; Armored Razzashi Raptor

/cast [flyable] Violet Proto-Drake; Armored Razzashi Raptor

Then there are some abilitys that are off the global cooldown, my warrior uses a macro like this to maximize shield block uptime while in combat.

#showtooltip Devastate

/startattack

/cast Devastate

/cast [combat] Shield Block(Defensive Stance)

I am going on a camping/hiking trip and will be gone from about the 5th of November until the 14th. I might be back sooner depending on weather or other factors. Have fun.

I was digging through my old screenshots wondering when exactly I started playing this game and here's what I found:

My oldest screenshot ever. It's of my warrior Caar leveling near Loch Modan.

My earliest screenshot of my druid Nuitarin is this one. I'm apparently admiring my first ever guild tabard in the city of Darnasus. So it looks like I have been since about July of 2005, how fun is that?

Nuitarin's current interfaceThis is a screenshot of my interface while tanking Hodir on 7-17. I labeled most of the addons I use where they show up on the picture. Its mostly standard except I have a feral specific addon called FeralByNight. It provides a frame that suggests what move to use depending on how much rage/energy you have and what debuffs are on the target. Its usefull for cat dps but not so much for bear tanking. It also has a proc monitor to tell when trinkets/idols/enchants activate. I use the following macro along with a separate button for maul and demo roar to do most of my tanking on a single target:

/castsequence reset=6 Faerie Fire (Feral)(), Lacerate(Rank 3),Mangle (Bear)(Rank 5), Swipe (Bear)(Rank 8),Lacerate(Rank 3)

This keeps FFF and Mangle on cooldown almost always and maintains Lacerate on the target in most cases. Parrys and dodges by the boss when tanking in mitigation gear with low hit and expertise sometimes allows the Lacerate stack to drop, but using the macro helps my situational awareness.

I FRAPSed the hodir kill so you could see the interface in action: YouTube

These are some of the macros I use on my shaman:

This macro checks if I am in a group and in combat before using heroism. It also prints the message in raid chat for those too busy to see that I did, in fact, just use heroism.

#showtooltip Heroism
/stopmacro [nocombat]
/script local u,m = IsUsableSpell("Heroism") if u and not m and GetNumRaidMembers() > 0 then SendChatMessage(" >>> Heroism! <<<","RAID") end
/cast Heroism

This is a handy macro that will purge a enemy and clense a friendly, its good for saving a button space.

#showtooltip Cleanse Spirit
/cast [harm] Purge; [help] Cleanse Spirit

This is the macro I use to apply my earth sheild. I typically focus the tank when I heal so it checks for my focus target first. Then in order, if the focus doesnt exist or is dead or an enemy, uses my target for ES, if target is unfrendly, uses Target of target, and last if I have no target or focus, it puts ES on myself.

#showtooltip Earth Shield
/cast [target=focus,help, nodead][target=target,help,nodead][target=targettarget,help,nodead][noexists]Earth Shield

Since smart res doesn't (or didn't) work for my druid, I didn't install it my last UI build and I use this macro for resing people.

#showtooltip Ancestral Spirit
/cast Ancestral Spirit()
/script SendChatMessage("Resurrecting","Whisper","Common",UnitName("Target"));
/s Resing %t

I also use this macro for tidal force and LHW.

#showtooltip Lesser Healing Wave
/cast Tidal Force
/cast Lesser Healing Wave()

I use this macro for PvP to interrupt the enemy healer. Since wind shock isnt on the GCD, the stopcasting isn't really needed, but I left it in anyway.

#showtooltip Wind Shock
/stopcasting
/cast [target=focus] Wind Shock(Rank 1)

I use this macro to do a instant big heal if NS is up, otherwise just HW.

#showtooltip Healing Wave
/cast Nature's Swiftness
/cast Healing Wave()

This macro will use stormstrike or start your auto attack if SS is on cooldown.

#showtooltip Stormstrike
/use 13
/use 14
/cast Stormstrike
/startattack [harm]

And last, the most important and complicated macro of all time:

/focus

dont laugh, it saves typing.