The smoke at reactor 3 caused workers to evacuate. At 5pm it had decreased and Tepco engineers were trying to determine the cause. Temperature and pressure remained the same.

Japan Times says the focus of on-site work is to restart the separate cooling systems at each reactor to keep cores and spent rod pools from melting down.
Checking of electrical system at No. 2, the first to be reconnected to the power center from new cables, continued. Power to monitoring system and air conditioning may be completed Monday.
Prime Minister Naoto Kan said progress was slow but teady. "Now we see some hope of getting out of this crisis situation."

Two tanks arrived, tasked with clearing contaminated debris blocking access to key installations.
Smoke from No. 2- No comments yet on cause.

Digression- Economists say reconstruction in Japan estimated at $235 billion and a 5-year effort. Buffet is strong on investing in Japan.
Reconnecting and rebuilding of power grids may end rolling blackouts on Tuesday.
Car and some other plants are re-starting production as power and other needs are met.