How much money is being doled out in fees for every block right now? Every time I see a calculation of the profitability of mining taking in account your hardware and the number of Hash/s it does and subtracting energy costs and then the probability of finding a share and receiving 25BTC every block and so on... it never accounts for the money given in transaction fees (that will eventually be the only money given to miners when the stock of BTC reaches 21 million).
I'd like to make a more accurate estimate of how much money for MHash is actually being generated that takes the transaction fees into account. I can't find that info on Block Explorer. Does anyone have an idea of the magnitude of those fees?
There are some useful charts that show information about, amongst other things, fees per block.  Fees per block are currently trending downwards, but that is due to the additional hashing power coming on-line which means that blocks are being mined faster and so the average number of transactions (and hence fees) in an individual block is dropping.  Expect this to balance out sometime soon as the network takes account of the increased hashing power out there.

Right now, if you assume that transaction fees sit at around 0.25BTC per block you won't go far wrong.