Calculators for explaining retirement options to a group?

[Reddleman]

I'm planning on leading a workshop for teachers on the general ideas of investing for retirement. I have a few good options, but I'm looking for calculators to help show them impacts in terms of numbers and (hopefully) graphs.

What I'm looking for :
1. compound interest benefits with periodic reinvestment (importance of compounding and setting up direct deposit).  Would be nice if it had dividends reinvested impact too. 
2. impact of taxable vs. tax deferred (to show why they want to use tax deferred rather than savings/brokerage)
3. impact of fees on investment outcome (we have a few horrible 403(b) vendors and one reasonable one- I'd like to be able to show the impact)
4. Hopefully it/they will be (relatively) easy for newbs to use.  I'd like to give them the calculators to play with.  Things like FIREcalc are great, but pretty intimidating for many.

Please post your favorite resources, and let me know if there's anything obvious that I'm missing.

[Retire-Canada]

Showing someone the basics of using a FIRE calculator like cFIREsim is really powerful. It may have 60 functional options, but you can point out the 3 or 4 that matter to your target audience and they can use the calculator without delving deep into the more complex/arcane functions.