For a Custom-Tailored Trip, Whatever Your Niche

Seniors

* An advocacy group for the over-50 set, AARP (888-687-2277, http://www.aarp.org/travel) has travel-specific information on its site; AARP the Magazine, which has a travel section with a free online presence ( http://www.aarpmagazine.org/travel), is included in the $12.50 annual membership fee. The AARP Passport program through Travelocity (888-291-1757, http://www.travelocity.com/AARP/home) allows members to arrange discounted travel through the all-purpose booking site.

* Elderhostel (800-454-5768, http://www.elderhostel.org) is a nonprofit group that runs education-focused, all-inclusive "learning adventures" in more than 90 countries for travelers 55 and older. The associated Road Scholar program (800-466-7762, http://www.roadscholar.org) also is learning-focused; its trips are a bit higher-end.

Single/Solo Travel

* Connecting: Solo Travel Network (604-886-9099, http://www.cstn.org) offers info on single-friendly trips; enhanced membership ($35 a year) includes an additional database and a bimonthly newsletter.

* Solo travelers of the same sex room together -- and avoid the single supplement -- on tours through Rick Steves' Europe Through the Back Door (425-771-8303, http://www.ricksteves.com).

* TravelAloneandLoveIt.com ( http://www.travelaloneandloveit.com), run by longtime flight attendant Sharon Wingler, includes a helpful Q&A column and links to other solo-travel sites and the Tourism Offices Worldwide Directory ( http://www.towd.com).

* Those both single and attached can sign up for a trip buddy through Travel Chums (212-787-2621, http://www.travelchums.com). The free membership provides an info database, notification when someone else with similar travel criteria joins and access to subject-specific message boards. For $180 annually, you can post photos and send messages to other members.

* 2insteadof1 ( http://www.2insteadof1.com). The travel companion site's thorough Quickfinder feature lets you search member postings by travel date, destination and activities.

Students/Teachers

* STA Travel (800-781-4040, http://www.statravel.com) is the self-proclaimed "world's largest student, youth and budget travel organization," with databases of discounted flights, tours, rail passes and hotels, plus travel resources such as eco-friendly tours and user forums.

* The International Student Travel Confederation ( http://www.istc.org) is a nonprofit membership association endorsed by UNESCO that works with travel agencies focused on student, youth (under 26) and teacher travel. Its identity cards, available from http://www.myisic.com, provide discounts worldwide. The site also links to a worldwide embassy directory ( http://www.embassyworld.com), handy if your passport is stolen.

* The Web sites for travel publication companies Lonely Planet ( http://www.lonelyplanet.com) and Let's Go ( http://www.letsgo.com) provide blogs, downloadable playlists and RSS feeds in addition to country-specific info.

* Social networking sites such as MySpace ( http://www.myspace.com) and Facebook ( http://www.facebook.com), among others, can host forums and discussions about where to go and how to get there. There are specific travel-related pages, such as the STA Travel page ( http://www.myspace.com/statravel).

* Founded in 1947, the Council on International Educational Exchange (207-553-4000, http://www.ciee.org) lists high school- and university-level study abroad opportunities and "gap year" information, plus programs for teaching abroad.