Should Scotland be an independent country? (Stack Data)
Even with Don't Knows included it's level-pegging (48-48), so this rather helpfully breaks the little sequence of No-majority polls from before the Holyrood election. The fieldwork dates precede the ComRes / Scotsman poll, which means it was probably the first post-election independence poll. The bad news, though, is that the ComRes numbers I took from Wikipedia earlier weren't totally accurate - the No figure before Don't Knows were excluded was understated by 2%.