It seems they're having some effect not just against their targets but in spreading awareness and motivating people who feel otherwise powerless. Naturally we should expect resistance to petitions by means fair or foul but the fact remains, they were a large part of halting TTIP in Europe and on many other causes.
Post your timely and relevant petitions here. (Mods: feel free to move it to general discussion if there's popular support)
First up: https://forcechange.com/160436/tell-congress-overturn-citizens-united-people-for-the-american-way/