Should Buy Netbook instead of Desktop Computer

I been thinking to buy a mini notebook since my friend introduced his netbook to me. I do check out the Acer Aspire One netbook when it's first launched. However, I have no budget to buy a netbook yet because I just bought a desktop computer three months ago. I am quite regretted bought the computer, if I would know early about the netbook I probably would not buy a new desktop computer but definitely would get the netbook. So that I could bring it together when traveling.