Jfrog offer their artifactory repository manager as a cloud service.
Personally some of the default configuration choices ("fixing" metadata, etc) are just plain wrong, but you can configure it to do the right thing.
(Full disclosure: both jfrog and sonatype are partners of cloudbees (my employer))
Edit:
They offer a 30-day trial, and their pricing can be seen here.
与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
