Over the next five months, on tickets purchased by Nov. 13, Aer Lingus (800-474-7424) will fly you one-way between Chicago and Dublin for $99 (and I am not making this up). Ireland-bound travelers from New York or Boston will get the same $99 fares to Dublin starting Nov. 15.

Travelers to London, a much larger group, can also get great deals. Without a required date for purchase, a major “consolidator” (discounter) named Travac (800-872-8800) will be selling post-Nov. 1 flights to the English capital for $230 round trip from New York, $290 from Chicago and $410 from Los Angeles.

Another such firm, American Travel Abroad (800-228-0877), will be pricing round trips from New York to Paris or Rome at $329 or $380 (respectively); $375 or $412 from Chicago, and $397 or $441 from Los Angeles.

The packages that combine air fares and hotel stays get even better. From Nov. 1 until mid-December, round-trip air to London and a Bayswater hotel for six nights, with breakfast daily, will be sold from New York for $349 to $379 per person (and $50 to $150 more from other cities) by two Internet-only tour operators (they charge $20 more to accept a phone call). Contact Go-Today.Com or OffPeakTraveler.Com.

Arguably, a one-week air-and-land vacation to Ireland starting Nov. 1 is an even bigger bargain: $399 per person not simply from New York or Boston but also from Chicago and Los Angeles for not a penny more, including round-trip air, a car (stick shift) for a week with unlimited mileage and a booklet of vouchers entitling you to bed-and-breakfast for six nights at country guesthouses all over the Emerald Isle. As if leprechauns had intervened, those magical rates and features will be confirmed by a tour specialist, Sceptre Ireland, at 425-487-9632.

And we could cite many other stunners: a week in Paris, air and land, for $469 (Go-Today.Com); a week in Rome, air and land, for $539 (Gate 1 Travel, 800-682-3333); a three-night weekend in London (at the modest Barkston Gardens Hotel or Central House) for an astonishing $289 from New York, $429 from Detroit, Chicago or Denver, $489 from Los Angeles, San Francisco or Seattle (from Gate 1 Travel, 800-682-3333, or Go-Today.Com). All the rates we’ve cited for packages are per person, double occupancy, extending at least until mid-March, but with Christmas-season blackouts. Prices may fall even further as we approach the frigid months of January and February.

How permanent are these shock-’em-into-going policies for winter travel across the Atlantic? Most people will say they’re for this year only, brought about by economic slowdown and September 11 jitters. I’m not so sure. When the airlines enjoy a winter of flying almost 100 percent full, as they most assuredly will with these fares, they may also discover they’re doing better than when they took off near empty in previous winters. Off-season, every transatlantic carrier will become a cost-cutting upstart. Every airline will be a Southwest or a JetBlue.

In the meantime, what a travel boon for those of us who love the great capitals of the Old World. How can you afford not to go?