Quite possibly the least convincing one of these I've gotten:
My name is Annabelle Webb, I know that this mail might come to you surprisingly because we neither know each other nor has ever met. I got your contact details in my search for a reliable and neutral person to partner with me.
Work with me to receive a discountable contract Bank Guarantee on a United Nation Contracted projects in Darfur, Sudan, Pakistan, Afghanistan, Iraq, Ethiopia, Indonesia, Malaysia,India and Haiti which has been completed and commissioned and you will receive 30% of the total value of the Bank Guarantee.
Details will be furnished to you when you indicate your interest in partnering with me in this life time venture.
Please contact me urgently.