You can get lots of good information on the Commuting subforum. You can commute on any bike, particularly a flat route of 8 miles. However, in the spirit of N+1, don't let that discourage you from getting an additional commuting bike. I would start out riding a bike you already own, and then figure out what would work best for you. I've been bike commuting for 8 years, and my round-trip commute is about 31 miles (22 initially). I started out commuting on an Italian racing bike that I had on hand, and later switched to touring, sport touring and cyclocross bikes. I've carried my gear using backpacks, racktop bags, large seatbags and panniers. Currently I am using a racktop bag. I've also used various LED battery-powered lights over the years, but currently using a dynamo light system.