I have stumbled upon some cool AP mashup threads in the past.
Where someone is talking about/running a game where they interweave multiple Adventure Paths together.
Some I have seen
- Rise of the Runelords with Skull&Shackles
- Skull&Shackles with Serpent's Skull
- Shattered Star with Rise of the Runelords
Now I am asking you, what are some of the best AP combinations you have thought of?