Not sure if this is of value to anyone, but I thought I'd put together a little Javascript / AJAX balance checker. Feel free to borrow or steal the code.
Basically, you put the Bitcoin Account or the FirstBits into the query string, and out pops the balance, along with an estimate value in US dollars.
The values for current balance, recent price, and bitcoin address given the FirstBits, are all retrieved by the client using Ajax.http://btcbal.comhttp://btcbal.com/?17chk4u81QdP26e8ieHWhhTsVF4RQh8fAhhttp://btcbal.com/?17chk4uSample output:
Bitcoin Balance for 17chk4u
17chk4u81QdP26e8ieHWhhTsVF4RQh8fAh
Current Balance: 0.001 Bitcoins
Recent Price: $21.43 per Bitcoin (weighted 24 hour average)
Value: $0.02
Conversion to other currencies is an exercise left to the reader.
Of course, it's dependent on the reliability of blockchain.info's API.