Here's one more special offer for your genealogical feasting this St Patrick's weekend.
MyHeritage will give you free access to its collection of 604,596 records of passengers who arrived in New York from 1846 to 1851 ie covering the key years of the Great Hunger. In addition to advising details of the ship they sailed on, these records provide the following information: name, age, last residence, destination, passenger arrival date and occupation. Many records contain additional detail.
Free access is available here and will continue until 23:59hrs (EST) on Monday 17 March. There's no sign-up/registration required.