As you can see I have about an 8-10 inch softwood 'sucker' (is that the right word) growing right along side of the main hardwood trunk of this fig tree.

I would be interested in having some recommendations as to what I should do with it...

Keep it,
cut it and discard
try to root it?

etc.... ?

Thanks  

By the way... the hardwood (not visible in the picture because it is leaning over...) is about 3 feet tall.

You have two good choices:

1) leave it and let your fig grow into bush form with 3-5 main trunks.

2) let the sucker harden, then separate it from the main tree with a sharp spade this fall and pot it up as a new tree.

I would decide based on zone. If you are in 8 or higher, grow the fig as a tree - thus separate the sucker. If you are in zone 7 or lower, grow as bush form. They tend to do better with cold winters.

     Gene gave you two good options above...if you go for option #2, then as your waiting for the wood to harden off, see if you can encourage some root growth at the base of the sucker by burying that area a little deeper in potting mix...this will allow you to tease off a small amount of root mass when you seperate the sucker from the main trunk, giving you a better chance at successful transplanting...good luck.