By Jim Donovan: How would you like to fly to Hong Kong for $100 round-trip? Well that’s the deal that Cathay Pacific is offering to promote its new nonstop route between Chicago O’Hare and Hong Kong that takes off beginning Sept. 1.

So what’s the catch? Well, first off the fare is only good from Chicago. (But at that price, even adding in the cost to fly to the windy city makes it a great deal.) Secondly, only 100 of the $100 fares will be offered.

Here’s how the promotion will work:

Starting today, Cathay Pacific will put 25 of the $100 tickets up-for- grabs each Thursday through the end of the month. Customers must go to Cathay Pacific’s special “100 tickets for $100” page, where the ticket window will officially open at 4:25 p.m. Eastern time. The first 25 people to click the PURCHASE NOW button will get the deal. This will be repeated three more times, also at 4:25 p.m. ET on the next three Thursdays (July 14, July 21 and July 28). That 4:25 p.m. ET.

You may be wondering why did they pick the 4:25 p.m. time for people to buy tickets, well that is the time that the Chicago to Hong Kong flight will depart. (3:25 p.m. Central)

The $100 fare includes all taxes and fees and all travel must be ticketed and completed by Dec. 31, 2011.

Here is the link: