I don't know if you can put borders around these, but there's this:
http://www.wowinterface.com/download...mbmonitor.html
Or you could set up something like WeakAuras or PowerAuras to watch your target for your Living Bomb debuff. (weak auras should let you set up a timer bar for it, plus you can use the addon to set up notifications for other spells/debuffs like Ignite.)
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"You'd be surprised how many people violate this simple principle every day of their lives and try to fit square pegs into round holes, ignoring the clear reality that Things Are As They Are." -Benjamin Hoff,
The Tao of Pooh