I have several old addresses that I have previously used for faucets (or in the case of my first address, for mining as well).  I would like to sweep the funds from those addresses into a new address.

Is there some way to get or estimate the transaction size prior to initiating the transaction?  These addresses have lots of small deposits, so I would like to transfer them to one address whilst minimizing the fees.  I mean, I would rather donate them to, say, maybe /r/bitcoin, instead of lose most of the funds to transaction fees.

If it helps, here are the current Balances and Number of Transactions for the addresses:

0.00017593 (16)
0.00243568 (361)
0.00799525 (101)
0.00972206 (264)