Lunch with a friend
Get out of your office or your cubicle, step away from your desk and invest time in building relationships and partnerships with people. This thing, the entire life and our careers and businesses within it is a people game first. Everything always starts with people so look for ways to build partnerships, synergies and proactively resolve any difficulties or challenges in person.
Invite your colleagues and partners out to lunch and you will see that the value of those 60-90 minutes will quickly surpass weeks (or even months) of e-mails which have been sent back and forth.