My gimmicks:
1.There's always one certified nutcase running around...a crazed hermit, a zany gnome...an eccentric alchemist...
2. A dive tavern called The Boring Pig.
3. One real nice, decent inn for the PCs to rest their heads.
4. There's no such thing as a generic "plus-something" melee weapon. Each of my magical swords, hammers, maces, spears, axes, and even some daggers, have a name and powers. No two are exactly alike. My youngest son's Wood Elf Ranger wields the long sword "Orcslayer", while my wife's cleric of Talona uses a heavy mace called "The Persuader", and a friend's Fighter carries the two-handed sword called "Screaming Brute".
5. The tendency for relatives of NPCs to pop up. The party defeated a priestess of Cyric named Evah Rigo. In a new Realms campaign with new characters, they are going to meet her son, Dagaton, the result of a union between Evah and a demon.
6. The tendency to name villains after people I know. Evah Rigo is a close approximation to the name of my wicked aunt.
7. Like computer programs, each of my adventures has a "back door"....if you can think creatively, and get a little lucky, you can bypass a lot of needless crap and hit the heart of the matter.
8. As a corollary to #7, there's always at least ONE escape hatch. Trick is, finding it and knowing when to use it.
9. Rock song references pop in a lot, as well as inside jokes. My current campaign has a female halfling named Tessie Dropkicker. To make it worse, she has a cousin named Vinitar Dropkicker.