Absolutely nothing, 150,000 miles later. All I've ever done is change the oil every 3000 miles.
Not a luxury car by any means, but its been paid off for a year and it still runs like new.
I am ready to trade in my 98 LX Accord for a new or used car. I bought it new and now have 308k miles, mostly trouble-free. Put in a new manual transmission at 249k. Still get 30 mpg, but now burning oil. Great car.