To get there, take any S-Bahn or the U5 and get off at the Ostbahnhof train station. If you want to go to Kultfabrik/Optimolwerke either follow the signs, or the stream of teenagers.
Deutsches Museum - Museumsinsel 1, Phone: +49 (0)89 / 2179-1, Fax: +49 (0)89 / 2179-324,  Hours: Daily 9:00 Am - 5:00 PM (For closures and other information see ) - One of the biggest and best-known museums for science and technology in the world. Admission: Adults € 8.50, Students and children aged 6 - 15 € 3.
Gasteig (near Deutsches Museum) is the place to go for first rate classical concerts given by the renowned Munich Philharmonic Orchestra.
Haidhausener Augustiner Wörthstraße 34 (Located on Bordeaux-Platz), Phone: +49 (0)89/ 4802594, Fax: +49 (0)89/ 4801825, Hours: Daily 10:00 AM - 01:00 AM
There is a Nachtkantine where you can eat, and stands selling kebabs (Döner in German) and the like.
Jazzclub Unterfahrt, Einsteinstrasse 42 (Take the U-Bahn to Max-Weber-Platz walk east from the station), ☎ +49 (089) 4482794, . Su. - Th. 19:30 - 1 h. Fr./Sa. 19:30 - 3 h. Concerts begin at 21 h.
This place is a 60,000 square-metre entertainment mecca. After Europe's largest disco complex - located in the terminal buildings of the former munich airport - had to close in 1996, the city had to find a replacement for the crowds of partygoers. It was called Kunstpark Ost (KPO) because of its location in a former industrial complex near the eastern railway station. Rumors about closing this area too started soon and according to the bills of its clubs and bars it should have been closed at least four times a year. In 2003 it looked as if the days of the KPO are really counted, so some of the clubs moved to an area 200m in the west called Optimolwerke. However most clubs on the original area (renamed to Kultfabrik) remained open and as always a few weeks later noone talked about closing it any more.
So Kultfabrik and Optimolwerke (and two more discos on the west end of the whole area) really are one big complex and most people do not distinguish weather they go to Kultfabrik, Optimolwerke, Kunstpark Ost or the "KPO" (pronounced like the English letters!). To have so many discos and clubs on a relatively small area is brilliant, because there is something for (nearly) every taste. And if you don't get into one, there is always another. But be warned that most of them may not be what you might expect from a big city like Munich. There are many visitors from outside munich who just took off their "Lederhosn" two hours ago and got in a pair of jeans to spend a night in the big town. And few of them are over 25 years old.
It does not get really full before about midnight or later, but if you come earlier you are more likely to get cheaper/free entry.
Babylon This is where the farmers around Munich spend their weekend. Italian pop music on Friday, techno on Saturdays.
Bongo Bar. This trendy bar lies in the heart of Munich's fun-centre Kunstpark Ost. In the red velvet surroundings and with delicious Thai cuisine - including cocktails - the guest can enjoy the evening in style. During the week there are cabaret acts and political/satirical singer-songwriters to be seen. Age group: 30-something.
Drei Türme Friedenstraße 10, Phone: +49 (0)89/ 450 288 17, Email: firstname.lastname@example.org  Hours: Wednesday - Saturday 10:00 PM - 6:00 AM - A usually cramped club. No fun if you are agoraphobic.
Harry Klein (Optimolwerke) A small club that hosts world-renowned elektro and minimal techno DJ's, also well known for the interesting visuals. Main acts usually only come on at 3am, even on weekdays. The club is sometimes called Marry Klein in winter. Entry price ranges from 5-10 euros. 
Keller Friedenstraße 10. Smaller club playing indie, emo, rock and alternative on friday, britpop and german pop on saturday. Age 18-25 
Nachtkantine. Grafinger Straße 6, If you need a warm meal and don't like to have a kebap or calamari in one of the many food stalls in KPO, this is your place. During the week the kitchen is open until 4 am, on the weekend until 6 am.
Rafael. Grafingerstr. 6, Phone: +49 (0)89/ 550 523 80, Email: email@example.com,  - Nice Club, not dark and dirty like many other clubs in KPO. Nice staff serving you great and resonably prices cocktails all night long.
Living 4 Grafingerstr. 6, Phone: +49 (0)89/ 4900-1260, Email: firstname.lastname@example.org,  - which plays popular R'n'B an Hip Hop
Freudenhaus with three different dance halls playing Pop/Hip Hop, German music (depending on he weekday) and techno. There you mostly find teenagers. (On Fridays, girls get into "Freudenhaus" for free before twelve).