fio is an I/O tool meant to be used both for benchmark and stress/hardware verification. It has support for 19 different types of I/O engines (sync, mmap, libaio, posixaio, SG v3, splice, null, network, syslet, guasi, solarisaio, and more), I/O priorities (for newer Linux kernels), rate I/O, forked or threaded jobs, and much more. It can work on block devices as well as files. fio accepts job descriptions in a simple-to-understand text format. Several example job files are included. fio displays all sorts of I/O performance information, including complete IO latencies and percentiles. Fio is in wide use in many places, for both benchmarking, QA, and verification purposes. It supports Linux, FreeBSD, NetBSD, OpenBSD, OS X, OpenSolaris, AIX, HP-UX, Android, and Windows.
I(2) Drive is an online storage solution that allows personal and corporate users to manage their important information from anywhere. It provides client and server software for accessing and sharing files through a Web interface and WebDAV clients either as a hosted service or an in-house install.
NBD-HTTP is a user-space tool that exposes a file read over HTTP as a local block device by using the network block device support in Linux kernels. Reading data from HTTP is done when needed, with read-ahead and connection reuse. One obvious use is to mount ISO images without having to download everything ahead of time.