Conan O'Brien has never met Sarah Killen (left) -- but he's helping pay for her upcoming wedding ... just by being her Twitter follower.
Killen tells PopEater companies have thrown free wedding rings, limos and wine at her since the late night host decided to randomly follow her last week.
Her shoes and dress will also be supplied by Kelima for $0 in exchange for promoting the company's favorite charity -- the Children's Hunger Fund.
Sarah says Conan's been invited -- no word on if he's R.S.V.P.'d.
