Reason
Software synthesis is just virtual equipment, generated on a PC, that you can play with like real toys. The industry standard is Pro Tools. I hate Pro Tools because it's too hard and over-complicated, but I love Reason. It's my flagship bit of software. I may sound like an advert for a product here, but it really is the bollocks. Reason was put together by Propellerhead Software in Sweden. It's a virtual rack with virtual kit in it. You can plug different bits of kit in all over the place and if you flip the rack around it's got a virtual spaghetti of digital leads bouncing around at the back. You have midi and audio controllers, a mixer (or two, or three). Effects hook directly into this. There's a loop player, two different types of sampler, a drum computer, two synths, loads of patching kit and multi effect units and the Matrix sequencer. In version 2.5, outboard gear including a massive distortion, digital reverb and vocoder were added. There's also room for a Rebirth Engine and some other interfacing through ReWire. Version 3.0 added a Mastering Suite and lots of cool new toys. Now on version 4.0, Reason ships with a huge sound bank for all its instruments, including an entire orchestra sampled especially for the NN:XT with the Ikea-esque name Orkester. It's easy to use, and there are so many options it makes your head hurt. I sync it to Cubase SX3 for the great DFH Drummer software you can use as a plug-in.

ReCycle
The Dr:Rex player in Reason needs .rex or .rex2 files to play. Rex files are different to standard .wav or .aiff samples because you can alter the tempo and pitch of the loop independently. ReCycle makes .rex2 files from standard bits of .wav file. It also has some handy tools you can use for writing. I'm using v2.1 at the moment, another Props product, as is...

ReBirth
ReBirth is a clever little bit of softsynth. The latest (and final) ReBirth has two Roland Bass Line 303s, a Roland TR-808 drum machine and  a TR-909, which was the upgraded version of the 808, with 'better' sounds.

Sound Forge
Sound Forge is a pretty special bit of digital stereo sound editing kit from Sonic Foundry. Sony took over the company a while ago, but didn't ruin it. Sound Forge makes loops for samplers and studio programs, edits and burns CDs, can clean up, add effects to, time stretch, enhance, noise gate and re-equalise all sorts of sounds, record stuff to hard drives, work with SMPTE and MIDI gear and is generally pretty darned fantastic. I then master on T-Racks 24.