I'm in the IS field for example, some professors take sabbaticals to consult on implementations/public policy/corporate IS strategy. They often have speaking engagements or workshops with corporations to both educate and add guidance to specific projects.
Really, though, how and where you consult is fully dependent on what you specialize in. If you specialize in something that doesn't translate well to corporate needs and rather operate in a niche that's interesting to you but not essential to the bottom line.. you won't find many opportunities.
Further, just being a professor at a T50 doesn't mean you'll be inundated with consulting requests; the opposite really. Consulting is a business and you need to operate like a business and generate leads for yourself.