I have a couple of really dull secrets that I keep from DH
First, DH doesn't know I'm on MN (been here for 6 years). I had a dream last night that my DH caught me on MN. I woke up in a cold sweat like I'd been caught out in an affair 
He wouldn't care, I think he'd just think it's a bit weird because we don't have children and he'd assume MN is for parents.
Second, I have a secret email account that I use for complaining to companies about shoddy products or service. DH is a really relaxed person and never lets anything get to him or phase him but I'm kind of up-tight and actually find it quite cathartic to voice my complaints about really mundane things. 
A friend was recently telling me that for the last few years she's told her DH that she goes to yoga on a Wednesday evening but she doesn't - she goes to an art gallery for a wander around then has a coffee and cake before jogging home (to look sweaty). Again, he wouldn't care but it's been too long now to tell him the truth 
Tell me what weird and completely inane secrets you've got from your DH...