The tech giant looks unstoppable right now.Alphabet (GOOG +1.02%) (GOOGL +0.99%) is part of the exclusive group of companies worth more than $1 trillion -- but there's only one member that has ever reached a$5 trillion market cap: Nvidia. However, in my view, there's a good chance that Alphabet will also be able to claim this achievement by the end of 2028.  It's not that far offAlphabet's current market cap is $3.8 trillion. So, the$5 trillion milestone doesn't seem out of reach at all. The stock would n ...