Do yourself a favor, Install a front rack
Last year I had a nasty crash while riding home from the bakery with a pie in my hand. I knew I needed to get some sort of rack for my bike. I would up welding one in my shop, it's made of steel and the platform is 12"x15" with cedar planks. I can't tell you how useful a simple front rack can be. I'm not talking about the skinny little bag support touring racks, I'm talkin' about a big flatbed rack, big enough for a case of beer or two. I like to throw an empty cardboard box from a case of beer and fill it with groceries, or veggies from the farmers market. Bolt one on your bike and I guarantee you won't regret it.
Check out some of these ready made options:
<a href="http://www.velo-orange.com/voporteurrack.html">http://www.velo-orange.com/voporteurrack.html</a>
<a href="http://www.cetmaracks.com/">http://www.cetmaracks.com/</a>
<a href="http://www.paulcomp.com/">http://www.paulcomp.com/</a>
<a href="http://www.waldsports.com/index.cfm/baskets.html">http://www.waldsports.com/index.cfm/baskets.html</a>