As an atheist I don't claim to understand what theists mean by a spiritual experience so I thought it would be interesting for us all to compare notes about what we could call in the loosest of definitions, spiritual experiences.
To start the ball rolling I will give a couple of examples.
1. Sitting in Glasgow Royal Concert hall with tears running down my face listening to kd lang singing hallelujah.
2. Standing in my back garden looking at Jupiter through a pair of binoculars for the first time and seeing not just Jupiter but its moons and knowing that the first person to ever see that sight was Galileo.