My favorite build is Power Treads, Drum of Endurance, Mask of Madness, Crystalis/Daedalus and then Assault Cuirass. I toss a BKB in there if I'm getting stunned all the time or add a Heart of Tarrasque if the game's going on for a ridiculously long time.
Really having fun with that build in Diretide currently, enemies are bunched up most of the time, so cleaving with God's Might + MoM + Crystalis is tons of fun.
Power Treads > Mask of Madness > Black King Bar > Assault Cuirass
That is what I usually go for. Sometimes I will get a Heart instead of the Assault though depending on the situation/team composition. I know some people go for BKB before MoM to make them useful in team fights quicker, but MoM allows him to farm the jungle with ease if he is in a tough lane against range.