Cyprus offers residency through investing 300,000 and citizenship (within 90 days) through investing 2.5 million(reduced to 500,000 after 3 years) in real estate.
Portugal offers residency through investing 500,000. After six years applicants and their families can apply for citizenship.
Spain offers a similar programme to Portugal but it's not possible to get citizenship unless residing in Spain for 10 years full time.
Greece offers residency through investing 250,000 in real estate but does not lead to citizenship.
Hungary offers residency through investing 300,000 in government bonds (refunded after 5 years). Citizenship in Hungary can be applied for after 5 years.
Bulgaria offers citizenship through investing 1,000,000 in government bonds (refunded after 5 years)which can be financed for a total outlay of 280,000.
Malta offers citizenship within a year, at a total cost of around 1.2 million (650,000 goes to the government). There are also a number of restrictions and screening interviews.