Amex has enlisted Hollywood actor Kevin Spacey to promote its 'Be Inspired' campaign, which will raise money for the charity established by Prince Charles to help disadvantaged young people.

The company has set up a Facebook page - compete with videos and photos - promising to give the trust 50 pence every time someone shares their inspirations. It is also tapping Twitter, donating every time someone uses the hashtag #amexbeinspired and offering Tweeters the chance to add a Be Inspired "twibbon" to their avatars.

However, as spotted by Bryony Taylor, the lack of control afforded by social media has left Amex open to abuse and some Twitter users have taken advantage of the hashtag to vent their spleen at the company.

A user called @piglungs has been prolific, offering 'inspirations' unlikely to endear him to the card giant, including: "#AmexBeInspired - You inspire other companies like yourselves to hide shit financial practice behind fake good deeds.

Another suggests: "#AmexBeInspired - You inspire me to make a list of the worst uses of social media I've ever seen. Which starts 1.#AmexBeInspired ..."

Others have joined in, with 'inspired' tweets railing against 'the total collpase of the financial services industry' and mischevious calls to take the campaign viral: 'Could we bankrupt them? [Amex] Let's try!'