I left the United States in May of 2000 with a 90-day round-trip ticket to London, and returned home in may of 2011 11 years and one week later.
I had no legal right to be in any European country for more than 90 days, and, in the theory of the newly-unifying European states, I would have no right to stay within the European Common Area, either, for more than those 90 days. But, due to my arrival during a historical period of change, I received no threat of deportation, and it was only when the Irish "decided" to realize that I'm not Irish that I was ever under any pressure to leave.
During my time in Ireland, the country took extraordinarily good care of me, treating me to a hospitality that went beyond their legendary "hundred thousand welcomes" to an absurd, nonsensical, and delightful extent.
I spent a about 2 years in the Netherlands,* six months in Spain, and 8 ½ years in Ireland.