In Android: Netrunner, Cyberfeeder is a piece of hardware that reads:
1 [Recurring credit]
Use this credit to pay for using icebreakers or for installing virus programs.
I'm interested in the "using icebreakers" clause. I know I can use it for icebreakers' paid abilities, such as
1 [Credit]: +1 strength or
1 [Credit]: break ice subroutine, but I was wondering if it can also be used for other effects like this one of Darwin's:
When your turn begins, you may pay 1 [Credit] to place one virus counter on Darwin.
Does "use" apply to this kind of cost, or just to paid abilities?