The S&P 500 (SNPINDEX: ^GSPC) is still in a bull market, which stretches back to October 2022. Since the U.S. stock market always trends higher over the long term, this might be a great time for investors to scoop up some bargains. The Roundhill Generative AI and Technology ETF (NYSEMKT: CHAT) offers diversified exposure to the industry through its portfolio of 37 top AI names, and investors can pick up a single share for under $40.