Note: While the last "balance" is the accurate number of bitcoins available to this address, it is likely not the balance available to this person. Every time a transaction is sent, some bitcoins are usually sent back to yourself at a new address (not included in the Bitcoin UI), which makes the balance of a single address misleading. See the wiki for more info on transactions.

c1830a7b4e... Block 173164 (2012-03-27 20:31:43) 21.5995 Received: Address 21.5995
bb81db2a00... Block 173174 (2012-03-27 21:58:08) 21.5995 Sent: Address 0