Here is a brief tutorial on how I create the recently updated bar on the left side of my main index template. I have three integrated blogs, with two of the blogs listing their last 5 entries.
In whatever blogs you want to excerpt (list the latest entries from) you need to create a new index template. In that template include this code:
<!This begins the include main blog excerpt!>
<div class="photobartxt">Latest Entries On Radio Free Blog</div>
<a name="<$MTEntryID pad="1"$>"></a>
<a title="<$MTEntryTitle$>" href="<$MTEntryLink$>"><$MTEntryTitle$></a><br />
<!This ends the include main blog excerpt!>
Change the “lastn” to the number of entry excerpts you want.
Save the file and make sure you have established a place for the file to be output (output as a text file).
On the template in which you want the latest entries listed include this ssi call: <!#include virtual="/path/to/include.txt">
You are done. You can do this with as many blogs as you want. In fact, I use the same technique to list my latest updates on a photo blog.