LaTeX

Why use Latex?

1. It makes reuse of figures, tables and equations across papers, presentations and posters very easy. For me, 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.
2. Latex is free. So if you can't afford Microsoft Office software, this is a good option.
3. 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.
4. 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.

Useful links

General

Latx project site

CTAN

Papers

Some journals accept papers in latex format. Check ahead of time.

Posters

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.

Talks

Here is a link with general information about latex presentations.

PPower4 is software that permits you to add powerpoint-like slide transitions to latex presentations. It generally requires that you use Adobe Acrobat reader to view your presentation with effects.