In Friedrich Lu's case, that hobby is suing local institutions. Over and over again.
Lu, a homeless man, has been filing federal lawsuits by himself, sometimes in hand-written complaints, since at least 1995 against, among others, the Boston Public Library, MIT, Harvard, the Harvard School of Dental Medicine, Dana-Farber Cancer Institute, Boston College, Suffolk County, the US Attorney's office in Boston, Boston Municipal Court and the Supreme Judicial Court.
Because he files pro se, it costs him relatively little. His opponents, however, have to assign lawyers to write briefs and motions and argue the cases in court.
To date, Lu has yet to win. In 2012, he did savor victory when a federal jury agreed a Boston College police officer had violated his rights in 2009 by frisking him during a search for an assault-and-battery suspect and awarded him damages - of one dollar. But the officer appealed and, just last week, the US Court of Appeals for the First District overturned the jury award, saying the officer had "qualified immunity" against a suit because he was properly conducting his job during an investigation into a crime.
Lu's latest target is the Boston Public Library, where guards apparently stopped him from bringing a rain-soaked grocery cart into the library in 2012. He filed one federal lawsuit over this alleged violation of his constitutional rights and, when things did not appear to go his way, a state lawsuit. Last week, the Supreme Judicial Court declined to get state courts involved in the matter because he's filed the same complaint in federal court.
Possibly in response, the next day Lu filed a new federal lawsuit against the city, alleging massive fraud by Mayor Menino and now Mayor Walsh to cover up what Lu says is the fact the BPL is not actually a city agency and should not be represented by city lawyers - a claim a federal court had already rejected. For good measure, Lu also named a long list of other city agencies as defendants, from the School Committee to the Boston Public Health Commission.