FeedReader
Simple, lightweight aggregator.

RSSOwl
Solid cross-platform RSS client.

Juice
Solid client for finding and subscribing to podcasts.

Pidgin
Connect to multiple IM accounts simultaneously in a single app, including: AOL IM, MSN, and Jabber. (formerly Gain)

X-Chat 2
Internet Relay Chat client.






aMSN
MSN client for multiple platforms