Maybe you can call him just to tell him you love him. Have you done that lately? or ever? I regularly hear from women who want their husbands to call them like this, but they never call him. Why not? Call him. And you are not permitted to say "I love you. Did you remember to pick up the clothes at the laundry?" The call is to tell him you love him. Just do it.
Maybe you can call him and invite him to lunch. Have you ever done that? You have to pay for it, by the way. That's part of the deal.
Maybe you can send him a card. Seriously, I have never seen a husband receive a card at work from his wife, but I think it would be great. Go get a loving card, like you would give to him personally, but send it to his office. Let it come in his mail. Let him get a smile at work from you.
Maybe you can send him a note that is loving or clever. You can use Facebook or e-mail or text messaging.
Send him flowers. Seriously. Send him candy. Send him something unusual. Let people at work know that he has a wife who loves him.
Maybe you can fix something special for the evening. It has to be something he would like to do with you (you can like it, too, of course).
Do something fun today. Make your husband smile today. You will be surprised at how surprised he will probably be.