I started working in Reason 3 about a month ago. I just posted a sampling of what I've learned so far. Here's some things I used

-Combinator (I find it more organized than Mastering Suite Combi)
-Mixer 14:2
-Line Mixer
-Malstrom (I decided to make some custom patches... I hate the preset synths)
-ReDrum
-MClass Equalizer
-MClass Maximizer
-Matrix Sequencer
-RV7000 Adv Reverb
-Digital Delay