Skill Mastery in E6?

[Zaq]

Does anyone know what sources of skill mastery (or any "take 10, even when you otherwise couldn't" ability) are available in an E6 setting? I think I used to have at least a partial list of them (maybe even a complete one, don't remember), but for the life of me, I can't find the bugger. I know that there's Changeling Rogue Sub Level 1, there's Hardened Criminal, and there's Warlock 4, but I can't think of what other ones come into play by ECL 6. (Oh, and expending psifoc to take 15 on Concentration, I guess, but that's rarely very interesting.) I could have sworn that there were at least one or two more sources, though. Does anyone else know of any other low-level sources of skill mastery or similar abilities?

[OldTrees1]

Skill Mastery is a Rogue Special Ability that can be accessed in E6 with the E6 specific Rogue 6 capstone feat.

[Zaq]

Skill Mastery is a Rogue Special Ability that can be accessed in E6 with the E6 specific Rogue 6 capstone feat.

I guess that's something. I was more looking for actual RAW abilities, though. (Sure, E6 is a set of houserules anyway, but that doesn't mean I like to use those houserules 100% as written, you know?) Still, I hadn't thought of that, so that's worth mentioning. Thanks.

Anything else? I could have sworn there are a couple other sources that you can get by or before ECL 6.

[Draz74]

Steady Concentration feat (Races of Stone).