If you're stuck between boats, you may want to walk inland from the harbor on Demosthenous or Vas. Georgiou to Plateia Korai, which leads to a cafe where you can sit with a book. If you want to be by the sea, stroll or take the no. 904 bus (.50€) from the Main Harbor to Akti Themistokleous, where you can also find cafes.
If you're in Piraeus in the summer, a more energetic suggestion is an open-air theatrical performance at the Kastella Theater, a few blocks inland from Mikrolimano. In 2000, the first Poseidon Festival, with a wide range of concerts, took place in Piraeus; it's becoming an annual event. Get details at Piraeus Municipal Theater, Ayiou Konstantinou (tel. 210/419-4550).
In the winter, performances are staged indoors, at the Public Theater on the green at Leoforos King Constantine. The Sunday flea market on and around Alipedou and Skylitsi is an equally crowded variation on the Monastiraki flea market, with generally lower-quality goods. The daily street market just off the Main Harbor is a good place to get picnic supplies for your boat trip.
The Maritime Museum (Akti Themistokleous), near the pier for hydrofoils (tel. 210/451-6264), has handsome models of ancient and modern ships. Don't miss the classical warship (trireme); scholars still don't know how all those oarsmen rowed in unison. The museum is open Tuesday through Saturday from 9am to 2pm; admission is 3€. If you have time, stop by the Archaeological Museum, 31 Harilaou Trikoupi (tel. 210/452-1598), to see three superb monumental bronzes, one depicting a youth (some say Apollo) and two of goddesses (some say Athena and Artemis). Museum hours are Tuesday through Sunday from 8:30am to 3pm; admission is 3€.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.