Looking for MSDS sheets?  Flinn is a good start:
http://www.flinnsci.com/msds-search.aspx

Our textbook (Glencoe Chemistry: Matter and Change, 2008) has a website, which has lots of resources for each chapter:

http://www.glencoe.com/sec/science/chemistry/mc/index.html
 

If you need word processing, spreadsheet, or presentation software, try Open Office (it's free!): http://www.openoffice.org

A great drill-and-practice website (especially for significant figures):

http://science.widener.edu/svb/tutorial/index.html

An on-line, free chemistry textbook: http://en.wikibooks.org/wiki/General_Chemistry

An interactive, on-line periodic table: http://www.webelements.com/

ChemTutor website: http://www.chemtutor.com/

Two Miss Gurganus-typed periodic tables:

With names

Without names

Lost your solubility chart or activity series?

There's lots of good help on balancing equations out there on the Internet:

• Balancing Act--It’s Elemental
• Practice Balancing Equations
• Classic ChemBalancer
• Balancing Chemical Reactions
• Balancing Chemical Equations
• Tutorial on Balancing Equations
• Chemistry Music Video 19: Don’t Break the Law
• Brain Boggle ChemBalancer
• Balancing Chemical Equations (requires Adobe Shockwave)

Density practice:

• Density and Buoyancy simulation

Iowa State Animations

Chem Collective

PhET Simulations

Virtual Activity Series activity

Types of radioactivity animation

Looking for chemical structures?

Try http://www.emolecules.com, type in your compound, and choose "Search."  You can then save the structure as a picture!

All you ever wanted to know about the periodic table:
http://www.chemistrycoach.com/periodic_tables.htm

Another periodic table:
http://www.lenntech.com/periodic-chart.htm

See the orbitals as animations here:
http://www.uky.edu/~holler/html/orbitals_2.html

Atomic orbitals animations: http://www.d.umn.edu/~pkiprof/ChemWebV2/AOs/ao1.html (you can spin and rotate them!)

S and p orbitals video

Electron orbitals video

Scandium electron distribution video (best orbital layering/animation I've seen)

Another orbital applet: http://www.falstad.com/qmatom/