Not enough years for a nice ring. Save that for 10 years.
Of course sending flowers is a given. Work or home which ever.
I usually don't call my wife at work, but I take a min out once a year and call her at work and tell her I love her.
Is there something you both enjoy doing outside the Bedroom that you could get a gift relating ? Buy each other bikes or Rollerblades or such. This says "I want to spend time with you"
Dinner that you plan out at a place that takes RESERVATIONS would be good.
If she's into girlie stuff, day spa's are nice as would a manicure etc.