Check out Monitor

Hans suggestion hits the bullseye, but Also consider PrintTemporary. It is not exactly what you asked for but it is useful as well for monitoring progress.

Regards,

Neil

I haven't tried Monitor, that could be better, but as another option I've been using my own little function for that forever:

pdr[expr_, symbols_List : {}, interval_ : Infinity] := 
 PrintTemporary[
  Dynamic[Refresh[expr, TrackedSymbols :> symbols, 
    UpdateInterval -> interval]]]

Before my code I use e.g. pdr[x,{x}], which shows x and updates whenever it does, or pdr[ListLinePlot[data],{},5] which updates a plot every 5 seconds, or whatever. It disappears when the block is done running.