Basically I think the most interesting is the "hybrid" approach, that uses several identifiable tactics and mixes them together. For example, you design a classic location-crawl, but you also have a timeline of things that are going to happen unless the PCs do something, plus you have random encounters (which could also be, more abstractly, random events), etc.
One term I'd come up with was the "man in motion"--the idea that in a setting (as opposed to a small location or adventure) you would include an entry in a random encounter table which, instead of pointing to a generic encounter ("2d6 gnolls"), would point to a subtable that includes a number of the named NPCs. So, while travelling on the road from Chartres to Bourges, you could run into Queen Catherine and her retinue (or whatever).
Another concept was the "extended encounter" as a substitute for normal random encounter tables. The "extended encounter" lies somewhere in between the random encounter out of the blue, and the static location-based encounter. The basic idea is that the GM defines a location, which can be as small or as large as you like, where the encounter will occur. However, instead of beginning with the parties rather close to each other, the encounter begins with a "detection phase", and is played out from there. For example if you enter a bear's hunting ground, you will "encounter" the bear in the sense of having to determine, based on your travel mode (cautious or hasty?), expertise (city slicker or woodsman?), etc., whether you simply run right into the bear, or if the bear catches wind of you (and reacts accordingly), or if you see signs of the bear (prints, droppings, animal carcasses, markings on trees) that let you take action, and so forth. In essence the process of "encountering" becomes (always) an extended contest that may or may not lead to a real confrontation followed by diplomacy, combat, flight, etc. (This idea is partly inspired by Magic Realm, the boardgame, and partly by an idea from old thread at theRPGsite that never reached fruition due to some Internet looniness.
However, I find that Zak Smith has already put together a long list of adventure design techniques that I've only just begun to digest, so....here it is.