curl -s https://raw.github.com/paulp/sbt-extras/master/sbt > ~/bin/sbt && chmod 0755 ~/bin/sbt

% sbt -v -210 -sbt-create about
Detected sbt version 0.13.0
Using $HOME/.sbt/0.13.0 as sbt dir, -sbt-dir to override.
# Executing command line:
$JAVA_HOME/bin/java
-Xmx1g
-jar
$HOME/.sbt/launchers/0.13.0/sbt-launch.jar
"++ 2.10.3-RC1"
about

[info] Setting version to 2.10.3-RC1
[info] This is sbt 0.13.0
[info] The current project is built against Scala 2.10.3-RC1
[info] sbt, sbt plugins, and build definitions are using Scala 2.10.2

Usage: sbt [options]

  -h | -help         print this message
  -v | -verbose      this runner is chattier
  -d | -debug        set sbt log level to Debug
  -q | -quiet        set sbt log level to Error
  -trace <level>     display stack traces with a max of <level> frames (default: -1, traces suppressed)
  -no-colors         disable ANSI color codes
  -sbt-create        start sbt even if current directory contains no sbt project
  -sbt-dir   <path>  path to global settings/plugins directory (default: ~/.sbt/<version>)
  -sbt-boot  <path>  path to shared boot directory (default: ~/.sbt/boot in 0.11+)
  -ivy       <path>  path to local Ivy repository (default: ~/.ivy2)
  -no-share          use all local caches; no sharing
  -offline           put sbt in offline mode
  -jvm-debug <port>  Turn on JVM debugging, open at the given port.
  -batch             Disable interactive mode
  -prompt <expr>     Set the sbt prompt; in expr, 's' is the State and 'e' is Extracted

  # sbt version (default: from project/build.properties if present, else latest release)
  !!! The only way to accomplish this pre-0.12.0 if there is a build.properties file which
  !!! contains an sbt.version property is to update the file on disk.  That's what this does.
  -sbt-version  <version>   use the specified version of sbt (default: 0.13.0)
  -sbt-jar      <path>      use the specified jar as the sbt launcher
  -sbt-launch-dir <path>    directory to hold sbt launchers (default: $HOME/.sbt/launchers)

  # scala version (default: as chosen by sbt)
  -28                       use 2.8.2
  -29                       use 2.9.3
  -210                      use 2.10.3 (or latest 2.10.x release or RC)
  -211                      use 2.11.0-M4 (or latest milestone)
  -scala-home <path>        use the scala build at the specified directory
  -scala-version <version>  use the specified version of scala
  -binary-version <version> use the specified scala version when searching for dependencies

  # java version (default: java from PATH, currently java version "1.6.0_51")
  -java-home <path>         alternate JAVA_HOME

  # passing options to the jvm - note it does NOT use JAVA_OPTS due to pollution
  # The default set is used if JVM_OPTS is unset and no -jvm-opts file is found
  <default>        -Dfile.encoding=UTF8 -XX:MaxPermSize=256m -Xms512m -Xmx1g -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC
  JVM_OPTS         environment variable holding either the jvm args directly, or
                   the reference to a file containing jvm args if given path is prepended by '@' (e.g. '@/etc/jvmopts')
                   Note: "@"-file is overridden by local '.jvmopts' or '-jvm-opts' argument.
  -jvm-opts <path> file containing jvm args (if not given, .jvmopts in project root is used if present)
  -Dkey=val        pass -Dkey=val directly to the jvm
  -J-X             pass option -X directly to the jvm (-J is stripped)

  # passing options to sbt, OR to this runner
  SBT_OPTS         environment variable holding either the sbt args directly, or
                   the reference to a file containing sbt args if given path is prepended by '@' (e.g. '@/etc/sbtopts')
                   Note: "@"-file is overridden by local '.sbtopts' or '-sbt-opts' argument.
  -sbt-opts <path> file containing sbt args (if not given, .sbtopts in project root is used if present)
  -S-X             add -X to sbt's scalacOptions (-S is stripped)