user78: Ideally, I'd like to see a pie chart with the whole pie being "Bitcoin-derived cryptocurrencies", and each major alternative represented as a market cap in Bitcoins and USD.
Currently, from what I gather we have:

Bitcoin - 7,415,750 BTC = $34,854,025 = 99.7%
Namecoin - 959,150 NMC = 25,897 BTC = $121,716 = 0.3%

I don't know where to get data on other cryptocurrencies right now, and if they even have any significant market cap.

user78: http://dustcoin.com/mining is the only site I know right now that shows this information.

user22: At the moment I don't believe there is any such site. It wouldn't be too hard to create, I might even do it myself, I just need to find a good data source for pricing.
The coin counts can be found easily here:

Bitcoin
Fairbrix
GeistGeld
I0coin
Ixcoin
Namecoin
SolidCoin
Tenebrix

Given an API to pull price data from, calculating the numbers would be trivial, after which it's just a matter of how pretty a chart you'd like. I have a question here if anyone knows of such a data source at which point I'd be happy to whip up just such a chart.

user78: Introducing ... Bitcoin Pie.
Supported Coins are Bitcoin, Tenebrix, NameCoin and SolidCoin. If your favorite coin is not supported, point me towards an active exchange (with or without an API), and a block explorer, and I'll integrate it.

78: <p>Ideally, I'd like to see a pie chart with the whole pie being &quot;Bitcoin-derived cryptocurrencies&quot;, and each major alternative represented as a market cap in Bitcoins and USD.</p>
<p>Currently, from what I gather we have:</p>
<ul>
<li><strong>Bitcoin</strong> - 7,415,750 BTC = $34,854,025 = 99.7%</li>
<li><strong>Namecoin</strong> - 959,150 NMC = 25,897 BTC = $121,716 = 0.3%</li>
</ul>
<p>I don't know where to get data on other cryptocurrencies right now, and if they even have any significant market cap.</p>
 78: <p><a href="http://dustcoin.com/mining" rel="nofollow">http://dustcoin.com/mining</a> is the only site I know right now that shows this information.</p>
 22: <p>At the moment I don't believe there is any such site. It wouldn't be too hard to create, I might even do it myself, I just need to find a good data source for pricing.</p>

<p>The coin counts can be found easily here:</p>

<ul>
<li><a href="http://blockexplorer.sytes.net/chain/Bitcoin/q/totalbc" rel="nofollow noreferrer">Bitcoin</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/Fairbrix/q/totalbc" rel="nofollow noreferrer">Fairbrix</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/GeistGeld/q/totalbc" rel="nofollow noreferrer">GeistGeld</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/I0coin/q/totalbc" rel="nofollow noreferrer">I0coin</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/Ixcoin/q/totalbc" rel="nofollow noreferrer">Ixcoin</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/Namecoin/q/totalbc" rel="nofollow noreferrer">Namecoin</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/SolidCoin/q/totalbc" rel="nofollow noreferrer">SolidCoin</a></li>
<li><a href="http://blockexplorer.sytes.net/chain/Tenebrix/q/totalbc" rel="nofollow noreferrer">Tenebrix</a></li>
</ul>

<p>Given an API to pull price data from, calculating the numbers would be trivial, after which it's just a matter of how pretty a chart you'd like. I have a question <a href="https://bitcoin.stackexchange.com/questions/1393/does-btc-e-have-an-api-for-alternate-currencies">here</a> if anyone knows of such a data source at which point I'd be happy to whip up just such a chart.</p>
 78: <p>Introducing ... <a href="http://bitcoinpie.com/">Bitcoin Pie</a>.</p>

<p>Supported Coins are Bitcoin, Tenebrix, NameCoin and SolidCoin. If your favorite coin is not supported, point me towards an active exchange (with or without an API), and a block explorer, and I'll integrate it.</p>
