Bankrupt Northwest Airlines Corp., in the process of laying off employees and cutting others’ salaries as it prepares to exit bankruptcy, published a booklet with a series of money saving tips. Included were suggestions that some employees found offensive, such as that included such suggestions as shopping in thrift stores, taking “a date for a walk along the beach or in the woods” and not being “shy about pulling something you like out of the trash.” The list 101 ways to save money was also posted for a time on its employee Web site. “We agree that some of these suggestions and tips … were a bit insensitive,” a Northwest spokesman said, and added that a revised version of the booklet was now available.