I'm riding pretty much along the same lines as B. Carfree. Don't remember the exact prices so below are approximate

Scotch lite reflective tape on back fender and crank arms. ($5)
Reflective vest (winter) reflective suspender type thing (summer) ($10 - $20)
Dinotte 400R rear light ($200)
Niter Rider lumina 650 - usually ride in the medium mode ($120)

The only times that I've thought cars don't see me usually involve rain and cars approaching from a side street coming off a stop sign where they don't quite plan on a complete stop and don't expect a cyclist. (think 35 degree rainy night)