I found a good one that holds most of the major alts which are worth mbtc or more per coin.
Exodus can handle Ethereum, Dash, Doge, Litcoin and of course Bitcoin.
It also has a nifty feature that lets you do an in wallet exchange of each coin using shapeshift which works out to be pretty cool. Because after you proceed with the exchange it timestamps that transaction with the price at the time of the exchange and then tells you the current price of that same transaction in live price rate. Every nice feature for those that are particular about the price you paid during the exchange like myself.
I use to do it in a spreadsheet to see how much I lost when the price spiked and now all the sudden rose when I wanted to go ahead and do an exchange. A real time saver for a price scrooge who cares about that sort of stuff.
The live price ticker of what you have currently in your wallet is also a nice feature as well.
Not sure what price they use to give that rate though.
That is something to ask the developers about on their ANN thread created by Omegastarstream on another thread in the exchanges section of the forum.
Not exactly a web wallet but a downloadable one with these features are really cool to have besides one that resides on the web like blockchain.info. That's for sure!