I occasionally do this as a routine for meditation/reflection/expanding perspective/entertainment/not sure what label to use, and I recommend it because I think members of the community will be able to do it.

I basically go outside and walk around looking around at trees the sidewalk and grass and trying to disassociate what I'm seeing from any notions of 'tree' or 'grass' object classes. Once I can get those I can usually extend it to everything in my perception. A sort of de-object-ification, trying to hold in my mind the notion that there are no boundaries between one thing and the next, and that 'thing' itself is a fundamentally false concept. If you read HPMOR, it's Harry's thought processes when he attempts partial transfiguration.

The effect is somewhat of an exhilarating experience of stepping out of the system and seeing it for what it is, and a peaceful intimate connection with the air around you, realizing that there really is no boundary between self and the world.

If I can point to anything similar, it would be Jill Bolte Taylor's description of her stroke, and drug experiences I've had recounted to me, though I don't have personal experience in either area.