Here are some links to websites devoted to grammar topics.  Some are designed for ESL/EFL students and others are for native speakers.  If you have any comments (positive or negative) about any of these sites which will help your classmates and future 005 students to select useful sites, please log in to the wiki and post them here below the link.

1. Ohio University ESL

http://www.ohiou.edu/esl/english/grammar/activities.html

2. Professional Training Company: Communication Strategies for Scientists and Engineers

"Good Grammar, Good Style Archive"

http://www.protrainco.com/grammar-archives.htm

(This is for native speakers.)

3. "English Conjunctions" by Linda Bryson

http://www2.gsu.edu/~wwwesl/egw/bryson.htm

4. Robin  Simmons' Grammar Bytes

http://www.chompchomp.com/menu.htm

(Interactive exercises, rules for fixing grammar problems; for native speakers)

5. HyperGrammar (David Megginson)

Univ. of Ottawa Writing Centre,

http://www.uottawa.ca/academic/arts/writcent/hypergrammar/

A complete electronic grammar course.

6. Jack Lynch's Guide to Grammar and Style

http://andromeda.rutgers.edu/~jlynch/Writing/contents.html

(for native speakers)