add spawn and channels examples

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diff --git a/Spawn/README.md b/Spawn/README.md
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+# Spawn
+
+Limbo supports the creation of processes operating on a given function via the `spawn` statement. Functions passed to spawn cannot have a return value.
+
+Inferno processes share memory with their parent processes which spawn them, bar the process's respective stack. Inferno processes are pre-emptively scheduled by the Inferno kernel. These processes are analogous, but not equivocal to, threads in unix-like systems. 
+
+Synchronization between processes is recommended to be done through [channels](../Channels).
+
+For further reading on potential inspirations for Inferno processes, see [rfork(2)](http://man.cat-v.org/9front/2/fork).
+
+## Source
+
+### spawn.b:31,40
+
+This section spawns four processes all of which will attempt to print to their standard output. Two functions spawn running the `quacker()` function and two function spawn running the `summer()` function with varying arguments. 
+
+Note: The call to `sleep()` in this context within the `init()` function. 
+
+## Demo
+
+	; limbo spawn.b
+	; spawn
+	quack!
+	Sum (2): 0
+	quack!
+	Sum (3): 0
+	Sum (2): 1
+	Sum (3): 1
+	Sum (2): 3
+	Sum (3): 3
+	Final sum (2): 3
+	Sum (3): 6
+	Final sum (3): 6
+	; 
+
+## Exercises
+
+- How many different orders do you see the print statements occur in?
+- What happens if you remove the sleep?
diff --git a/Spawn/spawn.b b/Spawn/spawn.b
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+++ b/Spawn/spawn.b
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+implement Spawn;
+
+include "sys.m";
+include "draw.m";
+
+sys: Sys;
+print: import sys;
+
+Spawn: module {
+	init: fn(nil: ref Draw->Context, nil: list of string);
+};
+
+summer(n: int) {
+	sum := 0;
+
+	for(i := 0; i <= n; i++) {
+		sum += i;
+		print("Sum (%d): %d\n", n, sum);
+	}
+
+	print("Final sum (%d): %d\n", n, sum);
+}
+
+quacker() {
+	print("quack!\n");
+}
+
+init(nil: ref Draw->Context, nil: list of string) {
+	sys = load Sys Sys->PATH;
+
+	spawn quacker();
+
+	spawn summer(2);
+
+	spawn quacker();
+
+	n := 3;
+	spawn summer(n);
+
+	sys->sleep(10);
+
+	exit;
+}