I confess to being an addict...

I check my net worth, my spending and saving progress, and my portfolio (combined from several different brokerage accounts) using Personal Capital at least once a week, sometimes every day ... after all, it's free and brilliantly organized.
Personal Capital has great tools for tracking spending (they can cut your spending by 15%), but what I love most is their automated financial dashboard -- it will look at all your assets and debts, tally up your asset allocation, project where you'll be at retirement, and suggest ways to manage risk or improve returns. It's free, I think their free tools are great, and I think it's worth checking out -- you can do so here.