Bunnycoin has a charitable voting system which includes a feature whereby 10% of all Bunnycoins mined go directly to user-voted charities utilizing Bunnycoin’s revolutionary decentralized charity voting and coin distribution mechanism. More info in the Bunnycoin thread at
https://bitcointalk.org/index.php?topic=595766.0I don't know about birdcoin or html coin.
I'm trying to invest these days in coins that offer "something extra" (plus Litecoin and Bitcoin of course). Bunnycoin's decentralised charity voting fits the "something extra" for me.