You don't need to sign up. There are no accounts. Just search your ethereum address or connect your wallet and you're off to the races. Here is an example - Bittrex's portfolio
Just like MyEtherWallet, except you can exchange tokens you own without manually creating transactions and sending them to an exchange
Well, we don't have your money, so no! Faast Portfolio is a client side app, meaning it only runs on your computer, not on our servers. Your web browser connects directly to an Ethereum node to send your transactions so we never see your private keys. It's also 100% open source for anyone to verify your money is secure.