Below are links to various samples I’ve come across or prepared over the years. All of them have been vetted for quality so no crappy MP3 transcodes here. 
Bourbon Breaks
A collection of classic drum’n'bass/jungle breaks, all collected from the original tracks on CD.
Download : 215mb zip
Drum Machines
A huge collection of samples from old drum machines.
Download : 700mb zip
Meanbeat Drumpack
A collection of decent, meaty drum samples.
Download :17mb rar.
Horns
A small collection of high quality brass samples.
Download : 9mb zip.