It´s not exactly the one on the picture that i used to go to the cruise but it was ok, comfortable and the staff was very friendly and nice. It took aroun 1 hour from Pieras to Poros. Time to have a coffe, sleep, relax and taking photos before arrive to Poros.
There are a few ferries daily between Poros and Piraeus. It takes almost 3 hours. There is also service between Aegina, Hydra, and Spetses.
A hydrofoil runs between Poros and Piraeus a few times daily. This takes only 1 hour. You can also take a hydrofoil to Hydra and Spetses.