What's that you said? You want to be able to practice your craft, but hate that your altar won't fit into your back pocket? Well, here's a nifty idea for you. Why not make a travel altar. As always with anything I write about, these little gems are very easy to customize to your individual needs. 
This is just an example of what you can do to make yourself a travel altar. Grab a small box , decorate as you wish or buy one ready made (this lovely box and it's contents are available at the Candle Wick Shoppe, everything is sold separately) and add whatever you would like to have in your travel altar. Try some oil, a tiny altar tile, incense, a gem, a small feather and sage,whatever is small enough to fit in the box you have chosen. The possibilities are only limited to what you can't think of or fit in your box.
It's incredibly convenient for those times when you have the urge to practice and you are away from your traditional sized altar. I've even seen travel altars made out of breath mint tins that were decorated! It's all up to the person creating it and what they want. So have fun with it. The sky is the limit.