(FORTUNE Small Business) – In the annals of boondogglery, can there be any greater hero than Senator John Glenn? A generation ago he orbited Earth three times at taxpayer expense, an arguably legitimate--if obscenely expensive--business trip. Some 30 years later, the aging senator, failed presidential contender, and onetime pal of savings-and-loan scoundrel Charles Keating got nasa to blast him into space again on the public's nickel. Presumably he was working on something crucial to the nation's well-being--like the effect of zero gravity on aging Democrats.

When the rest of us want to go somewhere and call it a "business trip," we have more to prove--to our investors, our accountants, or our consciences. And today's aspiring boondoggler has a harder time--at least with the Internal Revenue Service--than in the gilded age of expense accounting.

But there is hope. One corner of the huge conference industry is devoted to creating business trips that take you beyond the airport Hilton. Perhaps your strategic planning sessions would be more inspired in a Mongolian yurt or in the Antarctic. And if a small part of you has always identified with Dr. Strangelove, try staying at the Park Hotel Vitznau, near Lucerne, Switzerland, where you can rent a refurbished Swiss Army bunker for your next sales meeting. ("Today Safeway, tomorrow the world!")

The main obstacle, of course, is the IRS. Maybe you can dream up a meeting in Bali and get the company to pay for it (particularly if you own the company), but writing it off could be more complicated. Congress and the IRS have been steadily tightening the rules. "Remember when Jimmy Carter railed against the three-martini lunch?" asks Jonathan Howe, a Chicago tax attorney. "Well, Ronald Reagan gave us the 2.5-martini lunch, and Bill Clinton gave us the half-a-martini lunch."

Business meals, which once could be written off completely, are now only 50% deductible. And other nostalgic concepts, such as a tax break if your spouse went along, are gone. (Unless you--or your accountants--are really creative. A few years ago, Roy Disney convinced the IRS that it would hurt Walt Disney Co.'s image if he traveled on business without his wife.)

The goal, then: Convince the IRS that your trip was primarily intended to help you generate business. One rule of thumb, say attorneys: The more colleagues you bring, the more likely the IRS is to believe the trip was mostly about business. Your solo jaunt to prospect for clients in the Caribbean might draw suspicion, but if you bring along four employees, the feds will probably leave you alone. Another caution: Your expenses on a cruise-ship seminar are deductible only up to $2,000 a year, and then only on the rare U.S.-flagged ship.

The pros, for reasons we'll let you divine, seem to be doctors. Mountain Travel-Sobek (see the box below), for example, offers such seminars as wilderness medicine (at Mount Kilimanjaro) and hypothermia (in the Antarctic). Another group, Pacific Professional Seminars, is the dreamchild of Ernie Schmidt, an orthodontist whose goal is to fly-fish all over the world. He and his partners decide where they want to go, then find a medical expert to give a presentation. But it can be tough to find just the right expert. A proposed trip to Mongolia has attracted interest, says Schmidt, but he hasn't found an appropriate subject. So ... maybe Mongolia is hard. But if you're determined to satisfy your wanderlust, do not falter. The world awaits you.