Okay, seriously! This the perfect way of integrating all your blogs into one page. Having different columns for your different blogs. Not overdoing it by including all your 10 blogs on the same page, you can use this method to have a column for your Personal blog, with (say) your Cookery blog, and your Tech blog. Not many people try and use this, and that is why I wanted to just bring it up.
Yes! Blogger Help has a documentation about integrating your Blogger blogs into one place. Although the methods it has given, doesn't seem to work since I have tried them in the past. It says to include just the basic post format and then the one of the four lines based on your blogs configuration. However, none of them have worked for me, so I decied to provide my own methods of including multiple blogs with your mail blog.
Framing your blogs
The easiest and ugliest way to include multiple blogs is to include them in frames, or slightly neater, IFrames. The problem with IFrames being that browser compatibility is low, and they're virtually un-style-able (woo!! a new word! :D). The advantages being you can include any page in the IFrame and you can make all your changes to the blog seperately without affecting the display of your main blog.
I personally don't recommend this method, but its a good one to keep in mind.
Digest 'em feeds
This one is the easiest and almost perfect way of including a second blog. Just use Feeddigest's feed syndication to convert the feed of that blog to HTML, and then display it on your page. The advantages with this being that you need virtually no coding knowledge, and all your settings can be set automatically by Feeddigest for you. The look can be perfectly styled, and suited to your blog.
The downer being that unless you're paying for Feeddigest, your digest will not get updated that often. Hence, updates to your (side)blog will not show up immediately. It completely depends on the Feeddigest server. Also, their system is known to go down once in a while (due to upgrades or overload, or whatever reason they can throw at us). If you want immediate updating, this is the closest thing you can do to going manual and giving yourself the ultimate power, which brings me to my final method.
The best (if you're a power user) and most effective way to display posts from your other blogs on your main blog, is to take matters into your own hands. You can burn your ATOM into an RSS using Feedburner, and then use Stephen's fantastic XOXOTools to conver it to JSON. Then using a simple script, write it out on your page. Their is only one downfall, which is easy to avoid. You will need to code the script which writes out the data in the JSON. You could do that yourself, or ask someone (even me!) to write it out for you.
The advantages, on the contrary are major. You have complete control of whatever's happening. The display, positioning, styling, linking ... everything! The display is updated almost immediately (or as soon as Feedburner updates, which is very quick). This method is used to set up the "Latest Updated" (in the sidebar). I just leave out the post content, and display the titles for it. So you have a taste of what it can be like!
Having multiple blogs on one page really works to create awareness of your other stuff around the web, and helps you micromanage them properly. So go ahead, try it! :)