Even though my sig promotes my own stuff, I always try and at least offer something of value/humor/personal feeling when I post in anyone elses thread.

Apart for that one glaring exception (:crybaby, I also try and start threads that have the same.

I have NEVER sold my sig on ANY board because I have always had something of my own to offer.

I would suggest that if you have your own stuff and you promote someone else's in your sig one would have to question the value of what you have yourself to offer. I must say here that I have seen some program owners swap sigs for a bit of a laugh for a short time, but that is more for fun, and also has it's own value in public relations...

I DO click the sigs of others.

All the time.

I also like to know who I am dealing with on many levels, and I must say probably 50% of what I do I do through the boards and through board sigs.

So there is obvious value, and I won't kid you, I do post on several boards, and as time goes on my post count here will grow accordingly, and our sig being exposed is only a small, if not valuable, motivation for me to be doing that.

I just like the sound of my own voice

That's my 2c.