One-button multi-target healing

#showtooltip Healing Wave

/cast [target=mouseover,help,exists] [target=target,help,nodead] [target=targettarget,help,nodead] [target=player] Healing Wave

Healing Wave can be substituted for any heal or buff spell. If your mouse is over a player, pressing the macro will heal them. If your target or target's target is a player, they will be healed. Otherwise, you'll heal yourself.