I just tested Trimall. I don't see anything happening at all. Which is not surprising since all these memory recovery apps tend to do is swap everything out to the pagefile. Then the memory usage looks less for short while until the pages get brought back into memory again.
Here's the few quick tests of Trimall that I just ran:
FF memory after running TrimAll
Started by = C:\WINDOWS\Explorer.EXE
Virtual KB Curr = 580,452 Peak = 599,740
Working Set KB Curr = 194,380 Peak = 371,944
Page File KB Curr = 403,116 Peak = 435,160
System Pool KB Paged = 246 Nonpaged = 51
Private KB = 403,116
==============
FF mem after running TwimWS
Virtual KB Curr = 579,300 Peak = 599,740
Working Set KB Curr = 194,284 Peak = 371,944
Page File KB Curr = 403,292 Peak = 435,160
System Pool KB Paged = 246 Nonpaged = 50
Private KB = 403,292
==============
FF mem before running Trim programs:
Started by = C:\WINDOWS\Explorer.EXE
Virtual KB Curr = 569,684 Peak = 598,496
Working Set KB Curr = 194,584 Peak = 371,944
Page File KB Curr = 392,364 Peak = 435,160
System Pool KB Paged = 245 Nonpaged = 48
Private KB = 392,364
================
These stats from a program called TaskInfo
http://www.iarsn.com/taskinfo.html