ArbCruncher
I just wanted to share with this forum (so I hope you don't mind) a great little resource called "ArbCruncher", located at http://www.arbcruncher.com/
I've been using the basic calculator function for about 3-months now; it's cool but since yesterday, they seem to have put this online calculator on steroids - so that it now does a lot more number crunching.
Btw...if you have any interest you can check-out ArbCruncher by going to http://www.arbcruncher.com/betting_calculator.asp and as I said, this calculator can be used to work out
...so I hope you find it as useful a tool as I do! 
I've been using the basic calculator function for about 3-months now; it's cool but since yesterday, they seem to have put this online calculator on steroids - so that it now does a lot more number crunching.
Btw...if you have any interest you can check-out ArbCruncher by going to http://www.arbcruncher.com/betting_calculator.asp and as I said, this calculator can be used to work out
Multiback - arb an underround book, or dutch the likely winners.
Multilay - lay an overround book, or dutch the likely losers.
Back/Lay - trade on price movements, or exploit Back/Lay arbs.
Draw No Bet - hedge against the draw by backing both Win and Draw.
Parlay - calculate your winnings from permed bets.
Position Squarer - trade a selection into a breakeven position.
Permutator - calculate the number of available permutations.
Price Invertor - calculate the Back equivalent of Lay prices.
Layer's Aid - calculate your liability or how much you can afford to lay.
Multilay - lay an overround book, or dutch the likely losers.
Back/Lay - trade on price movements, or exploit Back/Lay arbs.
Draw No Bet - hedge against the draw by backing both Win and Draw.
Parlay - calculate your winnings from permed bets.
Position Squarer - trade a selection into a breakeven position.
Permutator - calculate the number of available permutations.
Price Invertor - calculate the Back equivalent of Lay prices.
Layer's Aid - calculate your liability or how much you can afford to lay.