Reverse cowgirl - Fairly common; you lie on your back, girl gets on top facing away from you with arms to the side of your shoulders or on your chest while her legs are straddled either side of your hips and you just drill fuck while you hold her hips or waist, with your legs bent for maximum thrust.
Sidewinder or corkscrew - get the good lady wife to lie on her back and then push her body up so that her back and legs are in the air, while she supports her back with her hands (so in effect she's resting her weight on her shoulders/upper back; place a pillow bellow her neck/shoulders for comfort) with her legs wide apart. Then you squat down and straddle her in a crucifix position with a leg either side of her body and fuck for all your worth.
Reverse handstand - Start as you would with missionary except with your lady's legs pressed against your chest. Grab her thighs and 'drag' her body up as you stand up to the point she is doing a handstand with her facing away from you. With your arms wrapped around her thigs, fuck her pussy or ass while she's in the handstand position. You can really get some thrust with this one; nice angle.
btw, how did the standing 69 go? Did your wife enjoy it.