Oh, I have quite a few, not in any particular order:
1 - Lethal Weapon: Hilarious, well done quadrilogy where the characters actually evolve over the series. Shame they finished at 4, would have made sense to have made a 5th one in 2002 when Murtaugh was supposed to retire, getting a 10 year extension at the end of the third film.
2 - Mexico Trilogy: Amazing to think the first film in the series only cost $7,000 to make. Then you have Antonio Banderas' badass one-liners in the other two.
3 - The Fast and The Furious: Really like cars and the series is like car porn so, yeah. The last two have actually been pretty decent from a critical point of view, apart from the 8 billion mile long runway at the climax of the 6th film. I rarely pick up on film mistakes the first time round but that was so obvious. Real damn shame what happened just over a year ago though, and how it seemed to be so goddamn funny to everyone, even though he wasn't the one driving and hadn't done anything that bad or life-endangering in the past.
4 - Mad Max: Similar reasons to the previous one. Weird to hear Mel Gibson with an Ozz-strayan accent though. Not looking forward to the reboot though.
5 - Evil Dead: One of those few films where horror and action are mixed perfectly. By the third one though Bruce Campbell had become a little too like Jim Carrey.