Uber Technologies (UBER 0.03%) has come a long way from its early days as a cash-burning disruptor of the taxi industry. Today, it's a profitable global platform with multiple engines of growth that span mobility, food delivery, logistics, and advertising.But after its share price has more than doubled in the past two years, the stock is no longer cheap. With a trailing price-to-sales (P/S) ratio of around 4.6, it's fair for investors to ask: Has the stock run too far ahead of its fundamentals?While the val ...