I've kept an informal list over the years, inspired by 8222's aircraft log in the signature - I thought it may be worth us compiling a list.
I'll start my list (going purely off memory and it's not a completed list) and will add to it.
Im not including historic railways and anything I'm mentioning, was in commercial service. 
101 BR
104 BR

142 Northern* and BR
143 Northern* and BR
144 Northern* and BR

150 GW
153 EM
155 Northern
156 Northern* and BR
158 Various Inc BR
159 SW

165 GW
166 GW
168 Chiltern
170 Various Inc Central

180 GC and GW

185 TPX
195 Northern

220 XC
221 XC and Virgin

314 SR
315 GA
319 Northern
323 WMR
332 HExp
333 Northern
334 SR
357 C2C
380 SR

390 Virgin

444 SW
450 SW

800 LNER
801 LNER
802 TPX

43 Various in BR
91 LNER* Inc BR
(Also got hauled by a loco ahead of a 91, on a diversion when lines were down on the ECML. Unsure of type unfortunately. Was in too much of a rush to notice by the time I got off).

994 TWPTE and Nexus

1973 Stock London Underground
1992 Stock London Underground
1995 Stock London Underground
1996 Stock London Underground
2009 Stock London Underground
D78
S7
S8

B90 DLR
B92 DLR
B2K DLR
B07 DLR

Bombardier Incentro AT6/5 NET

Bombardier M5000 Metrolink

Bombardier Flexity 2 Blackpool
English Electric Balloon Blackpool
Brush Rail coach Blackpool

Foreign:
NSB EI 9
NSB EI 11
NSB EI 17
NSB El 18

Prague Metro 81-71

NS DD AR
NS Class 1600

Renfe 463

TIB EMU (81?)

*Inc previous franchise holders.
*need to add other misc stock
Will continue to try and identify additional foreign stock too*