Try third parties like smooth ping might pay couple of $$ a month but cuts your ping in half some will let you trial for 30days before paying.
When I was playing WoW 24/7, I was paying $5 a month to 'Reducethelag.com' that cut my ping from 350ms to 120ms. Reduce the lag only works with WoW and Aion.
www.reducethelag.com
Might be hard finding one for a FPS game though but no doubt Google there is bound to be one around, some come as free unlimited but they never leave beta.

Better to pay a couple of bucks - $3 - 6 per month that's always stable. I dont have ping problems with FPS games only American MMO's as FPS always have servers available in Aussie.