I tend to go for the classic types of lava lamp, mainly Crestworth which were manufactured in the UK in the 60's and 70's (their heyday). They now trade as Mathmos. Most of my lamps are quite old but I do have some from the 90's and 2000's. I bought a cheapo lamp the other day on Ebay because I thought it looked quite pretty. It has that classic Astro shape (like lava world) only smaller and has purple casing with matching liquid and purple lava.