These two pipeline stocks have strong upside potential from here.While artificial intelligence (AI) stocks have been leading the market higher, it's not the only sector where good investment opportunities exist. One area where investors can find some hidden gems is in the pipeline space.Let's look at two master limited partnerships (MLPs) that you can invest in now. $1,000 can be a good starting point, and you can look to dollar-cost average more into them later.Energy TransferEnergy Transfer (ET 0.06%) has ...