Looking for an ability to sense creatures via telepathy

[Pleh]

I had a bit of trouble making it clear just through the title alone.

First off, this is a 3.5 game, but PF solutions probably will fit just fine if I backport them (I might need some help doing the backporting, as I'm not too familiar with the changes to and from PF). I'm the DM for this game, so I'm not too concerned with getting permission.

I'm looking for any ability (monstrous, spell like, etc) that might function like blindsense or lifesense, but only works for detecting thoughts (maybe it's a psionics thing).

I know there's the Detect Thoughts spell, but I was thinking less "reading surface thoughts" and more "sense creatures that are thinking nearby." Also that is a spell, not a native "sense" ability, which was more what I was thinking of.

Somewhere in the back of my brain, I feel like I've heard of an ability like this in the system (could just be a lingering illusion), but I'm not even sure what questions to ask in researching solutions online. Google Fu needs key words to work from and my lack of lexicon wasn't yielding any relevant results.

[Psyren]

Do you mean mindsight? You can find it in 3.5 Lords of Madness.

[bahamut920]

Yeah, Lords of Madness has the Mindsight feat, which requires telepathy and gives you the ability to passively detect creatures within its range, as well as giving you their creature types and Int scores. By RAW, I think that only mindless creatures are "invisible" to it, as telepathy isn't mind-affecting.

[Rijan_Sai]

Came here to mention Mindsight, too.
Its not with the "feats" section, though; it's "hidden" in the section talking about... aboleths, iirc.

Edit: Nope, I was wrong... it's the Tsochar, page 126!

[Pleh]

Excellent, yes. I think that is just what I was looking for.