Ok, this feat is not exactly "weird". I added the Skill Focus requirement as a kind of counterbalance to the feat's benefit (the same can be said about the limited uses per day). This feat is another attempt to simulate some of the tropes of fantasy and sword & sorcery fiction (without making the caster wait for spell turning and other similar high-level spells).
You can concentrate on a more powerful counterspell that lashes the dweomer’s energy against its original caster.
Prerequisite: Improved Counterspell, Skill Focus (Spellcraft)
Benefit: If your counterspelling is successful, the original caster suffers 1d6 points of damage per slot level of the countered spell. For example: a countered fireball would provoke 3d6 points of damage, while a maximized fireball would cause 6d6 points of damage. This damage ignore SR and there is no saving throw.
Eldritch Refusal can be used once per day, plus one more time for each 4 levels in spellcasting classes. You must declare the use of this feat before the counterspelling is resolved.