You can save as much as 35% in taxes on every dollar you pay in interest. In other words, your mortgage is tax deductible at your top tax bracket.
Using a house as part of business will certainly help, but you can only use part of the house as a business expense--the portion that you use as part of your business.
Paying off your mortgage completely will not necessarily give you the biggest tax advantage when use your business as part of the deductions.
I'm not a CPA so I must ask that you seek their counsel for the definitive answer.
Also, check out Ric Edelman's book, "Ordinary People, Extraordinary Wealth"
As previously mentioned, Ric Edelman is the expert on this and has done the study on this and now a lot of other financial planners and advisors are coming around to the facts presented in his argument. Plus, he's Oprah's personal financial planner--if it's good for her, it's certainly good for me and a lot of other people out there.
Check out the brother A and brother B scenario in the video on my site: http://ezleadcapture.com/member/wlg.htm
It clearly shows the power of compounding interest and how quickly it can create wealth for you.
