Suppose you have a simple products table:

id | name  | category
.......................
1  | prod1 | first
2  | prod2 | first
3  | prod3 | second
4  | prod4 | third
5  | prod5 | third

Note, that in this example "category" is a plain string, not a foreign key.

I've been trying to figure out if it's possible to render Form::select with optgroups basing on "category" field. I didn't find a ready to use method (like Collection::lists()), so I've written a little Form macro:

https://gist.github.com/marekmurawski/8855132

These macros would render selects with optgroups basing on the example table's category like this:

first
  prod1
  prod2
second
  prod3
third
  prod4
  prod5