You need very particular geography for pumped hydro, plus in hot dry climates your stored energy literally evaporates.
Hrmm, perhaps this isn't so feasible. Performing a clean & jerk of 95 pounds to a height of 7 feet would yield about 900 watt seconds of potential energy. So even if you had a very efficient laptop (15 watts) and perfect energy conversion, you'd have to perform a clean & jerk every 60 seconds to keep computing. Even if you were in good shape, you probably couldn't keep that up for more than a hour.