For the OBD1 (prefacelift) models, the high pressure ABS unit has a tendency to leak fluid and fail, there's also the distributor O-ring leak which is quite common.

Looking inside the engines, the valve seals and guides on the exhaust side tend to wear a lot with age particularly on VTEC B series engines, causing oil burn and blue smoke at high RPM.

Other than that and the previously mentioned issues I find these cars are holding up rather well with age. Certainly a lot better than S13 Silvias and some other sports cars of the early 90's.