I bought One Deck Dungeon from Asmati last summer and I played it on Sunday.
It’s a really enjoyable solo board/card game.
I don’t know much about solo games apart from T&T and Lone Wolf solos.
Anyone recommend any good solo board/card games?
The original Ogre by Steve Jackson worked very well solo. All you needed to do was write up some movements and actions on index cards, then draw them on the Ogre’s turn. Since it’s a single unit (the Ogre) against an army it worked a lot better than some games which required you to track multiple units
@Lordof1 is really your man for solo action. He plays with himself more often than not and may have more suggestions.
There’s literally hundreds of games that are good to play solo. For starters, almost any co-op game works as a solo game too. My current rotational crop of favourites includes Aeon’s End, Gloomhaven, Mage Knight,Flashpoint: Fire Rescue, Arkham Horror: The Card Game, Scythe, Terraforming Mars, but there’s so many that you probably need to narrow it down more - do you prefer shorter games? Longer? Narrative heavy or intricate mechanics? Tactically rich? You may want to check out the solo player guild at board game geek, I’m sure Roger can supply a link.
Very happy to help but you may need to narrow your request down a little!
That’s the 1 Player Guild on BGG.
But as Nick says, give us some idea of other games you already enjoy, or the rough sort of thing you’re looking for, and we’ll try to help.
Ok.
I like short games of 30-60 minutes that can generate narrative in my head.
I don’t want to have lots of components and really I like portable games I can put in my small messenger bag or the bottom of my small suitcase.
Probably not Renegade or Aeon’s End then. 
Onirim works quite well for this: it’s in a small box and there are plenty of variants. (But you need to like shuffling.) In a slightly larger box, Burgle Bros works very well solo. Railroad Ink would also be a candidate, but I found the opportunities so variable that beat-your-own-score isn’t really meaningful; others disagree.
That’s it for small boxes in my collection…
Friday might be a good choice for you - a solo only game, short and very portable, as it’s just a deck of cards.
Friday and Oneira look good.