Today I may not have time to perform my physical practice, but I will always try to incorporate yoga in some fashion. It may be that I my stop my small son squashing the bug in the garden or picking the beautiful flower from it's stem, or I may decide to avoid a negative train of thought. This is what the great yogic avatar Patanjali described as "Ahimsa" or nonviolence to all living beings (including yourself).
So I may not have contorted my body into an unusal shape or performed five sun salutations (which is still great fun), but yoga is still part of my busy day. This makes me feel happy.