A Deputy U.S. Marshal (DUSM) has one of the most diverse jobs out there. Other agencies are as diverse as the USMS, such as Customs and the FBI. However, in these agencies agents generally specialize in one type investigation or another. In the USMS I may carry avariety of cases at any given time, to include narcotic cases (MOU with DEA), escapes, violations of conditions of release (bail and the fed equivalent of parole) - they always go back to what got them there in the first place, any type of state warrants (through task forces and requests for assistance), warrants from a variety of OIGs.
In addition to investigations, we also are responsible for court security/threat investigations, witness security (witness protection), asset seizures, prisoner tranport, and pretty much anything the Attorney General wants.
We also have regional SRT teams as well as our national tactical team, Special Operations Group. Our SRTs handle high threat entries and escorts at the local level, while SOG handles duties at eh national level. Our regional SRT has recently acted as a Couter Assault Team (CAT) on the transport of some outlaw bikers who were planning an escape. Even more recently, our SRT did an explosive entry for a HIDTA search warrant. A good link for some SOG history can be found at: http://www.specwarnet.net/taclink/Federal/USMarshals_SOG.htm
Also, the DUSM referred to above that frequents Hawaii is not the norm. That duty is a isolated to the one California district. And, as to transporting prioners to/from other states... well , this is minimized for the most part, too. Most often the USMS uses JPATS for prisoner transport. It is better known as ConAir.
Go to the lecture is you can. It should be interesting. Also, if you're lucky, it will be a Deputy U.S. Marshal at the lecture as U.S. Marshals are appointed and not career positions... hence, the Marshal may or may not have a whole lot of LEO experience.
Feel free to hit me up if you have any more questions.