it's easy to miss argentum, but it's got some promise hidden behind it. ARG is a sister currency to Digitalcoin and Securecoin; all three are under the same development, which is very active. CryptoAve.com, a $USD capable exchange has been under development for the past several months and is scheduled to go into open beta very soon. It's not difficult to understand how this will support the currency.. in the short term ARG, SRC, and DGC especially, are very good buys.
check out the subreddit if you want some quick info on what's going on behind these three coins:
http://www.reddit.com/r/digitalcoinIRC is the best place to get updates, though be prepared to hang around for a while:
https://kiwiirc.com/client/irc.freenode.net/#digitalcoinyou'll probably find the most information in the forums:
http://digitalcoin.co/forums/