Why use LaTeX?
- It makes reuse of figures, tables and equations across papers, presentations and posters very easy. For some, this is the main motivation of using LaTeX. .eps files scale well so you can just include the same figure in papers and posters and you don't have to (usually) worry about bizarre scaling effects. Equations are even nicer.
- LaTeX is free. So if you can't afford Microsoft Office software, this is a good option.
- LaTeX works with BibTeX to make doing references very easy. Again, BibTeX is free unlike Endnote which is a common software package for use with Microsoft Office.
- There's lots of online information about how to do stuff in LaTeX.
The primary disadvantage of LaTeX is the learning curve associated with using LaTeX. So those new to LaTeX would benefit from either giving themselves extra time to prepare their first LaTeX document or having a friend who knows LaTeX and who doesn't mind answering a lot of questions.
LaTeX software packages
BibDesk is a nice frontend for managing your library of references (ie your BibTeX library). It even autofiles your library of PDFs which makes maintaining and searching your collection of papers much easier than before.
Some journals accept papers in LaTeX format. Check ahead of time.
Here is a link with a source file for making posters in LaTeX. The cls file can be modified to alter the style of the poster.
Here is a link with general information about LaTeX presentations.