diff --git a/076-postgres/076-postgres.go b/076-postgres/postgres.go
similarity index 84%
rename from 076-postgres/076-postgres.go
rename to 076-postgres/postgres.go
index 5fbc186..62dbcb4 100644
--- a/076-postgres/076-postgres.go
+++ b/076-postgres/postgres.go
@@ -1,11 +1,11 @@
+// ## Postgres
+
 package main
 
-import (
-	_ "github.com/bmizerany/pq"
-	"database/sql"
-	"fmt"
-	"time"
-)
+import _ "github.com/bmizerany/pq"
+import "database/sql"
+import "time"
+import "fmt"
 
 func main() {
 	db, openErr := sql.Open("postgres", "dbname=gobyexample sslmode=disable")
@@ -50,16 +50,7 @@ func main() {
 	fmt.Println(dropRep)
 }
 
-// == running
-// # start postgres
-// $ createdb gobyexample
-// $ cd xx-postgres
-// $ go get
-// $ ./xx-postgres
-
-// == todo
-// connection pooling
-// concurrency
-// re-connection
-// errors
-// explain
+// todo: connection pooling & concurrency
+// todo: re-connection
+// todo: errors
+// todo: database_url
diff --git a/076-postgres/postgres.sh b/076-postgres/postgres.sh
new file mode 100644
index 0000000..6bc1a7b
--- /dev/null
+++ b/076-postgres/postgres.sh
@@ -0,0 +1,10 @@
+# First, be sure that you've installed Postgres
+# and have a server running locally at port 5432.
+
+# Then create an example database.
+$ createdb gobyexample
+
+# Now install the dependencies for the postgres
+# example and try running it.
+$ go get github.com/bmizerany/pq
+$ go run postgres.go
diff --git a/077-rand/077-rand.go b/077-rand/077-rand.go
deleted file mode 100644
index 4256166..0000000
--- a/077-rand/077-rand.go
+++ /dev/null
@@ -1,37 +0,0 @@
-package main                        // The `math/rand` package provides psuedo-random
-                                    // numbers.
-import (
-	"math/rand"
-	"fmt"
-)
-
-func main() {
-	fmt.Print(rand.Intn(100), ",")  // For example, `rand.Intn` returns a random `int` n,
-	fmt.Print(rand.Intn(100))       // `0 <= n < 100`.
-    fmt.Println()
-
-	fmt.Println(rand.Float64())     // `rand.Float64` returns a `float64` `f`,
-	                                // `0.0 <= f < 1.0`.
-                                    
-    s1 := rand.NewSource(42)        // To make the psuedo-random generator deterministic,
-	r1 := rand.New(s1)              // give it a well-known seed.
-											   
-	
-	fmt.Print(r1.Intn(100), ",")    // Call the resulting `rand.Source` just like the
-	fmt.Print(r1.Intn(100))         // functions on the `rand` package.
-    fmt.Println()
-
-    s2 := rand.NewSource(42)        // If you seed a source with the same number, it
-	r2 := rand.New(s2)              // produces the same sequence of random numbers.
-	fmt.Print(r2.Intn(100), ",")                  
-	fmt.Print(r2.Intn(100))
-	fmt.Println()
-}
-
-/*
-$ go run rand.go
-81,87
-0.6645600532184904
-5,87
-5,87
-*/
diff --git a/077-rand/rand.go b/077-rand/rand.go
new file mode 100644
index 0000000..cebe697
--- /dev/null
+++ b/077-rand/rand.go
@@ -0,0 +1,39 @@
+// Rand
+
+package main                        
+                 
+// The `math/rand` package provides psuedo-random
+// numbers.
+import "math/rand"
+import "fmt"
+
+func main() {
+    // For example, `rand.Intn` returns a random `int` n,
+    // `0 <= n < 100`.
+	fmt.Print(rand.Intn(100), ",")  
+	fmt.Print(rand.Intn(100))       
+    fmt.Println()
+
+    // `rand.Float64` returns a `float64` `f`,
+    // `0.0 <= f < 1.0`.
+	fmt.Println(rand.Float64())     
+	                                
+    // To make the psuedo-random generator deterministic,
+    // give it a well-known seed.                                               
+    s1 := rand.NewSource(42)        
+	r1 := rand.New(s1)              
+											   
+	// Call the resulting `rand.Source` just like the
+	// functions on the `rand` package.
+	fmt.Print(r1.Intn(100), ",")    
+	fmt.Print(r1.Intn(100))         
+    fmt.Println()
+
+    // If you seed a source with the same number, it
+    // produces the same sequence of random numbers.
+    s2 := rand.NewSource(42)        
+	r2 := rand.New(s2)              
+	fmt.Print(r2.Intn(100), ",")                  
+	fmt.Print(r2.Intn(100))
+	fmt.Println()
+}
diff --git a/077-rand/rand.sh b/077-rand/rand.sh
new file mode 100644
index 0000000..1f9f06f
--- /dev/null
+++ b/077-rand/rand.sh
@@ -0,0 +1,5 @@
+$ go run rand.go
+81,87
+0.6645600532184904
+5,87
+5,87
diff --git a/078-rate-limiting/078-rate-limiting.go b/078-rate-limiting/rate-limiting.go
similarity index 56%
rename from 078-rate-limiting/078-rate-limiting.go
rename to 078-rate-limiting/rate-limiting.go
index 83aa109..c8d1879 100644
--- a/078-rate-limiting/078-rate-limiting.go
+++ b/078-rate-limiting/rate-limiting.go
@@ -1,6 +1,8 @@
+// ## Rate Limiting
 package main
 
-import ("time"; "fmt")
+import "time"
+import "fmt"
 
 func main() {
 	throttle := time.Tick(time.Millisecond * 200)
@@ -10,6 +12,4 @@ func main() {
     }
 }
 
-
-// == todo
-// credit http://code.google.com/p/go-wiki/wiki/RateLimiting
+// todo: credit http://code.google.com/p/go-wiki/wiki/RateLimiting
diff --git a/079-redis/079-redis b/079-redis/079-redis
deleted file mode 100755
index e8faebf..0000000
Binary files a/079-redis/079-redis and /dev/null differ