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.