I have ran on the track of Withdean and walked on part of the pitch on the same day. I was taking part in a junior Sussex athletics event there a year ago.
Withdean - A few times
Port Vale - Did the REMF flag before the match after we won div 2 and were on the pitch un folding it (kind of counts)
Grimsby - When we got relegated.
Goldstone - A few times
Wembley - Concerts
Rochdale - protest against Bellotti in main stand culminated in several of us walking around edge of pitch to get to him, even though it's highly unlikely we would have done much other than hurl abuse. anyway we got chased by stewards and home fans called us into their end, where they prevented us from getting ejected.
Bognor - in 87 or 88 saw them knock Exeter out of FA Cup 1st Round. as kids me and my mate joined the hundreds of other fans to go over the gloat at the City fans. i think that same day one of their fans climbed up a floodlight, although that may have been Torquay in the next round!
Goldstone (numerous down the years, celebrating and protesting)
Withdean (couple, all celebrating promotion)
Doncaster (protesting)
Rochdale (protesting)
Shrewsbury (celebrating promotion)
Leyton Orient (transferred from one stand to another).
Southampton (last game at Dell)
Bournemouth (hastily erected wall at front collapsed)
Goldstone
Ullevi Stadium Gothenburg (Aberdeen winning European Cup winners cup)
Pittodrie
Tynecastle
Lincoln
Grimbsby last season walking to the press box
Withdean
Hampden loads as a kid
Ran on with all my mates after we beat York City 7-2 around '75-76 I think. MOTD cameras were there so it was the done thing to run on wearing a parka & wave yer scarf. My Mum went mental when she saw me!
When we beat Cheaterfield for the title, I ran on the pitch and my shoe got stuck in the mud and came off So I carried on running. And some big bloke in a leather jacket picked me up and bear hugged me.
A bit later a mate rung me and said Did I just see you on Sky Sports news running accross the Withdean pitch with one shoe on
Went on the Goldstone pitch in May 1977 when BHA got promotion v Sheff wed (pm KO, 6th may i think, won 3-2, 32,000 people there)
Been on the pitch loads of times at Withdean because i used to work for Ecovert and that involved going to Withdean on a friday to try to get rid of the puddles....that was several years ago tho'