All right, folks. It's a fact that the skill synergies in the basic 3.5 PHB can be somewhat lacking. So, we're looking to expand them a bit. If you have an idea, feel free to post it here!
As an example… Currently, Sense Motive and Bluff ranks don't support each other at all. This seems rather silly to me. If you have a good inkling of how to lie, you no doubt understand that others are likely to lie to you as well, and your knowledge helps you stay on guard against them as you subconsciously pick up on tricks and techniques. (5 ranks in Bluff = +2 Sense Motive)
Sense Motive tends to get the short end of the stick, as well. I wouldn't mind seeing synergies with it and Intimidate and Gather Information, as well, but right now, we're talking Bluff. When you start paying close attention to people's mannerisms, it quickly becomes apparent how many little lies are inherent in social interaction, and how many tells people broadcast. Being aware of these can allow you to better perpetuate your own lies, noting where your target is uncertain, judging how open they are to your explanation, etcetera. (5 ranks in Sense Motive = +2 Bluff)
Any other ideas?