NEW YORK (TheStreet) -- How will a Greek default affect European banks? That's what a viewer tweeted Jim Cramer Thursday.

Speaking from the floor of the New York Stock Exchange he said it will be very bad and that's why he wants investors to sell Deutsche Bank (DB) - Get Report, even though the firm probably doesn't have a ton of exposure.

Many companies are going to take a hit, with Italian banks being the most exposed, he warned, so investors should be careful. However, Cramer said he doesn't like them at all.

On investing in Bed Bath & Beyond as a housing play, Cramer said he could understand that thinking in theory but noted Bed Bath has been getting squeezed by Target (TGT) - Get Report, a holding in his charitable trust, Action Alerts PLUS, and Wal-Mart (WMT) - Get Report. He said you can play housing through Target as well as Costco (COST) - Get Report. Investors are fleeing Costco because the momentum, the chart and the stock are so bad, Cramer said, but that's precisely what makes him want to rush in.

Asked about Hewlett-Packard (HPQ) - Get Report after it divides into two companies he predicted you will see some value for a short time but the slowing PC market will continue to get worse. Since that will weigh on HP he can't recommend the stock.

Cramer said he made an adjustment on Twitter, (TWTR) - Get Report another AAP holding. He had seen Twitter potentially heading to $29 to $31 but he now believes the $35 level may hold.

At the time of publication, Jim Cramer's charitable trust Action Alerts PLUS held a position in TGT and TWTR.