Tough day at the office? Feeling stressed? You need a breath of fresh air. But stepping outside isn't really an option in polluted Hong Kong. You could shell out for a trip to an ultra-hip oxygen bar - or reach for an Oxy-gene oxygen bottle and mask. This portable, environmentally friendly, refillable unit provides 20 litres of oxygen, enough for 15 minutes. Part of the proceeds from sales of units and refills are donated to the Clean Our Skies Foundation. Bottles can be ordered by e-mail at [email protected]. Units cost $350 and refills $89.