Entries 14 and 15 are my favorites of yours. For the graphic on 15, I'm trying to figure out exactly what it is...Is there any way to integrate the "I" for Interlock and the "S" for sourcing into the graphic? I like the other two as well, but they are reminding me too much of the recycling symbol. Thanks for the entries, they are great.
Think of taking your 2 hands and interlocking your fingers together. (one palm down and one palm up) That's the visual I was using when I created the icon. Symbolizing "interlocking" with the use of the "I" and the "S". It is abstract so look at it closely and it will come to you.