I was looking for a simple way to get RSS alerts through IM for a homebrew application I was working with and came across iNeZha. In a nutshell iNeZha is an RSS bot that automatically takes RSS and delivers it through a couple mediums. That means you can subscribe to an RSS feed and have the summary and link delivered to you through your Google Talk client.
I had a very specific need for this which I wont go into but I thought it was worth mentioning since this is one of the only ones I could find that supports Gtalk & email.
Check it out at www.iNeZha.com and let me know what you think.