Romulan is out of this galaxy (pun intended). It's very very close to being a pure Indica. It's slight gene variation might be what makes it a unique and therefore popular weed to smoke. It's popularity probably boosts around the time of Star Trek conventions. For those of you who pride yourselves on your complete ignorance of anything remotely Star Trek (including the entire SyFy channel), Romulans are a fictional race of aliens.
Romulan the weed, unlike the people, has broad dark leaves covered in crystals. It almost looks like galactic royalty. (That's the last "Trek" reference.) It smells and taste of an earthy pine. It's not as spicy as many Indica's.
It's high is spatial. It will send a warm buzz through your body, almost forcing you to relax. It has a unique head effect for an Indica. It can be used as a really great downtime weed.