Step right up, ladies and gentlemen! Perhaps you'd like a rare touring map of Idaho from the '50s, or an exquisite travel alarm clock! No? Well, how about a 12-volt portable oven, a New Delhi wall calendar, or even a fare card good for $33 worth of travel on Washington, DC's subway system?

All that and more is available in the travel section of the nation's attic, eBay.com. Everything from vacation condo rentals to airline tickets. Are there good deals? There are -- but, be careful.

For example, I found a couple of United upgrade certificates -- good for domestic and international flights -- with starting bids of $75. Now, these are tough-to-get certificates are given to United's most frequent flyers, those who fly at least 100,000 miles a year.

But do your homework before bidding. First of all, two of the certificates I found on line expire in less than two weeks -- on the last day of March. Secondly, while the sellers correctly state that their coupons are valid for most fare categories, the important word here is most. If you hold a very cheap, advance-purchase ticket you may not qualify for an upgrade, even with this magic certificate. Fare categories are identified by letters, H, Q, Y -- as many as a dozen of them. One of the most common advance-purchase fare categories is designated by the letter K, and it's not up-gradable on United with one of these coupons. So, know your ticket's fare category before you bid. Or, make sure, when you buy your coach ticket, you ask for a fare category that qualifies for an upgrade.

One other footnote: United Airlines stipulates that these coupons are void if sold. That's why, when you click on purchase details, you'll find the seller is selling something like -- and here I quote -- "one white envelope." Ah, but in that envelope just happens to be a United, system-wide upgrade certificate -- good, old American ingenuity.

What else is available? Well, cruises galore at prices that are often, but not always, below retail. In fact, from the pictures of cruise ships that accompany many of the descriptions, I'm guessing some travel agents are using eBay as another vehicle for selling. A piece of Hartmann luggage that's normally several hundred dollars, new, had a starting bid of $15. But from the photos, the latches seemed to be missing. There are 21 pages of time-share offers, like 7 nights in a condo in Mazatlan, Mexico, with a floor bid of $400. Though it's offered by someone with an eBay name of "cheaponthebeach," there's no evidence the condo is on the beach.

After spending hours online, I can tell you that if you look for travel deals as eagerly as I do, you'll have a ball browsing eBay's travel section. Just be sure to read the fine print and do the numbers.

From the Savvy Traveler, I'm Rudy Maxa for Marketplace.

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