Morning Money Memo:

Are we heading into another tech bubble? Some investment experts are warning that some technology companies are overvalued, bringing back memories of the Nasdaq bubble in 2000. "There are some pockets of exuberance," Scott Kupor of the venture capital firm Andreessen Horowitz tells The Wall Street Journal. Tech startup values are setting records. The Chinese phone maker Xiaomi is the world's biggest startup this year, worth more than $45 billion. The company is the leading player in the world's largest smartphone market.

Shake Shack is bringing its burgers, milkshakes and crinkle-cut fries to Wall Street. The burger chain filed for an initial public offering, hoping to raise as much as $100 million Shake Shack has grown rapidly since opening a single outlet in Manhattan's Madison Square Park more than 10 years ago.

China is blocking access to Gmail. The government is limiting or maybe even banning Google services in China. The Foreign Ministry in Beijing claims it doesn't know anything about the block. Data from Google's Transparency Report show online traffic from China to Gmail fell precipitously Friday and dropped to nearly zero Saturday, although there was a tiny pickup Monday.

Professors from three leading British universities say policies favoring international debt repayment over social spending contributed to the Ebola crisis in three West African nations. An article in The Lancet Global Health journal claims that IMF policies prevented an effective response to the outbreak that has killed nearly 8,000 people. The IMF denies the charges, saying health spending had increased in Sierra Leone, Guinea and Liberia, if counted as a percentage of their economies.

The cost of being uninsured in America is going up significantly next year for millions of people. It's the first year all taxpayers have to report to the Internal Revenue Service whether they had health insurance for the previous year, as required under President Obama's health law. Those who are uninsured face fines, unless they qualify for one of about 30 exemptions, most of which involve financial hardships.