Evening boat trips from Jinja run upstream towards the Source of the Nile and back, usually timed for sunset. The Nile here is wide and calm close to the lake, and the light in the late afternoon turns the water copper. Herons, kingfishers, and fish eagles are common along the banks; hippos occasionally surface in the shallower inlets. The trips run about two hours and include a cold drink.
Several guesthouses and tour operators along Nile Crescent organise these daily. They're popular with travellers who've done the white-water rafting and want something to do with their second evening — and they offer a genuinely different perspective on the river than standing on its banks or being hurled down its rapids.